phd thesis on zno nanoparticles

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Synthesis of ZnO nanoparticles by two different methods & comparison of their structural, antibacterial, photocatalytic and optical properties

Md Jahidul Haque 1 , Md Masum Bellah 1 , Md Rakibu Hassan 1 and Suhanur Rahman 1

Published 16 March 2020 • © 2020 The Author(s). Published by IOP Publishing Ltd Nano Express , Volume 1 , Number 1 Citation Md Jahidul Haque et al 2020 Nano Ex. 1 010007 DOI 10.1088/2632-959X/ab7a43

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1 Department of Glass & Ceramic Engineering, Rajshahi University of Engineering & Technology (RUET), Rajshahi-6204, Bangladesh

Md Jahidul Haque https://orcid.org/0000-0001-7945-5937

• Received 23 December 2019
• Revised 3 February 2020
• Accepted 26 February 2020
• Published 16 March 2020

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In this work, two different methods (sol-gel and biosynthesis) were adopted for the synthesis of zinc oxide (ZnO) nanoparticles. The leaf extract of Azadirachta Indica (Neem) was utilized in the biosynthesis scheme. Structural, antibacterial, photocatalytic and optical performances of the two variants were analyzed. Both variants demonstrated a wurtzite hexagonal structure. The biosynthesized variant (25.97 nm) exhibited smaller particles than that of the sol-gel variant (33.20 nm). The morphological analysis revealed that most of the particles of the sol-gel variant remained within the range of 15 nm to 68 nm while for the biosynthesized variant the range was 10–70 nm. The antibacterial assessment was redacted by using the agar well diffusion method in which the bacteria medium was Escherichia coli O157: H7. The zone of inhibition of bacterial growth was higher in the biosynthesized variant (14.5 mm). The photocatalytic performances of the nanoparticles were determined through the degradation of methylene blue dye in which the biosynthesized variant provided better performance. The electron spin resonance (EPR) analysis revealed that the free OH · radicals were the primary active species for this degradation phenomenon. The absorption band of the sol-gel and biosynthesized variants were 363 nm and 356 nm respectively. The optical band gap energy of the biosynthesized variant (3.25 eV) was slightly higher than that of the sol-gel variant (3.23 eV). Nevertheless, the improved antibacterial and photocatalytic responses of the biosynthesized variants were obtained due to the higher rate of stabilization mechanism of the nanoparticles by the organic chemicals (terpenoids) present in the Neem leaf extract.

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1. Introduction

As a rapidly growing sector in materials science, nanotechnology and nanoscience deal with materials that have particles within a size range of 1 to 100 nm and a high surface-to-volume ratio [ 1 ]. In general form, these particles are termed as nanoparticles (NPs) which exhibit highly controllable physical, chemical and biological properties in the atomic and sub-atomic levels. However, these unique features create opportunities to use them in different sectors such as electronics, optoelectronics, agriculture, communications, and biomedicine [ 2 , 3 ].

Although, several NPs are showing their effectiveness in different sectors of technology, but zinc oxide (ZnO) NPs have gained much more importance in the recent years due to their attractive and outstanding properties such as high chemical stability, high photostability, high electrochemical coupling coefficient and a wide range of radiation absorption [ 4 ]. Again, ZnO NPs are also recognized as n-type multi-functional semiconductor materials that have a wide band gap of 3.37 eV and exciton binding energy up to 60 meV even at room temperature [ 1 ]. Nowadays, ZnO NPs are predominantly used as antimicrobial agents, delivering systems vaccines and anti-cancer systems, photocatalyst, biosensors, energy generators and bio-imaging materials [ 5 – 7 ]. Among themselves, the photocatalytic application of ZnO NPs is significant. However, the photocatalytic performance of ZnO NPs can be significantly enhanced by adopting two ways. The first one involves the reduction of particle sizes by using efficient synthesis methods, while the second one involves the change of structural morphology by the incorporation of several elements (such as metal, non-metal, noble metal, transition metal, etc) into the crystal structure of ZnO NPs. However, in this work, we will proceed by adopting the first one.

Several fabrication techniques are used to produce ZnO NPs such as thermal hydrolysis techniques, hydrothermal processing, sol-gel method, vapor condensation method, spray pyrolysis and thermochemical techniques [ 8 ]. Nevertheless, recently a new synthesis method has been introduced and that is called biosynthesis scheme in which the NPs are prepared by using biological materials having significant reducing and stabilizing features. Moreover, NPs with variable size and shape can be achieved through this process.

Researchers proposed several possible plant extracts and fungal biomasses that were used in the green synthesis of ZnO NPs such as Aloe Barbadensis Miller (Aloe Vera) leaf extract [ 9 ], Poncirus trifoliate leaf extract [ 10 ], Parthenium hysterophorus L. (Carrot grass) leaf extract [ 11 ], Aspergillus aeneus [ 12 ], Calotropis procera latex [ 13 ], Sedum alfredii Hance [ 14 ], Physalis alkekengi L. [ 15 ], etc. However, the smaller particle size of ZnO NPs was observed by using Poncirus trifoliate leaf extract (8.48–32.51 nm), while for others, the results were satisfactory. In addition, another potential element for the preparation of ZnO NPs through the biosynthesis method is considered to be a leaf extract of Azadirachta indica (Neem leaf). The leaf extract contains highly active phytochemicals and enzymes that participate in the oxidation or reduction reactions that occur during the fabrication method and manipulate the bulk ZnO to convert into ZnO NPs [ 16 ]. Moreover, Neem leaf provides significant biological restrictions against bacterial growth and fungal growth [ 17 ].

The present study focused on the preparation of ZnO NPs by two different methods. The first one is the sol-gel method, while the second one is the biosynthesis method in which the Neem leaf extract was used as a mandatory element. A comparison of the properties (structural, antibacterial, photocatalytic and optical) between the two variants of ZnO NPs was performed. Here, the sol-gel synthesized and biosynthesized ZnO nanoparticles were nominated as ZnO A NPs and ZnO B NPs respectively.

2. Methodology

2.1. materials.

All the starting raw materials including zinc acetate dihydrate [Zn(CH 3 COO) 2 .2H 2 O, Merck Specialties, India], sodium hydroxide [NaOH, Merck Specialties, India] and absolute ethanol [CH 3 CH 2 OH, Merck Specialties, Germany) were maintained at a high purity level (>99%). However, in the biosynthesis method, another raw material was also used and that was the leaf of Azadirachta indica (Neem leaf).

2.2. Synthesis of ZnO nanoparticles (ZnO A NPs) by sol-gel method

At first, 20 gm Zn(CH 3 COO) 2 .2H 2 O was mixed into 150 ml distilled water and stirred for 20 min at 35 °C to produce a zinc acetate solution. Again, 80 gm NaOH powder was weighed, mixed into 80 ml water and stirred for around 20 min at 35 °C for producing NaOH solution. After mixing both solutions, the titration reaction was performed by the addition of 100 ml ethanol into the drop-wise manner accompanied by vigorous stirring. The stirring was continued for around 90 min to complete the reaction for obtaining a gel-like product. Then the gel was dried at 80 °C overnight and calcined in an oven at 250 °C for 4 h. Finally, ZnO nanoparticles were prepared. However, the overall chemical reaction for the preparation of ZnO nanoparticles by using NaOH can be expressed as:

2.3. Synthesis of ZnO nanoparticles (ZnO B NPs) by biosynthesis method

At first, the neem (A. Indica) leaves were collected from the Azadirachta Indica trees on the campus of Rajshahi University of Engineering and Technology, Bangladesh. After washing with distilled water, the leaves were dried into a dryer for 24 h. Then 20 gm dried leaves were smashed and mixed with 50 ml distilled water. After that, the mixture was stirred by a magnetic stirrer and heated at 60 °C for 1 h. As the mixture displayed a yellow color, it was filtered using the Whatman TM filter paper. However, the extract solution was used for further preparation of ZnO nanoparticles. The overall process for the preparation of Neem leaf extract is stereotyped in figure 1 .

Figure 1.  Process flow diagram for the preparation of Neem leaf extract.

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The next step included the preparation of the zinc acetate solution. For this, 21.94 gm Zn(CH 3 COO) 2 .2H 2 O was mixed into 50 ml water and stirred for 20 min at 35 °C. Similarly, in order to prepare a NaOH solution, 4 gm NaOH powder was added into 50 ml distilled water and simultaneously stirred for 20 min at 35 °C. Both solutions were then mixed by vigorous stirring. During this stirring process, the neem leaf extract was drop-wise mixed with the solution. As the addition of neem leaf continued, white precipitation of nanoparticles appeared. Then the solution was filtered and the filtered product was dried at 80 °C for 4 h. After that, the dried powder was calcined at 250 °C for 4 h and grounded to obtain the desired ZnO nanoparticles.

2.4. Characterization of ZnO NPs

X-ray diffraction was performed for structural analysis employing 40 kV-40 ma (scanning step of 0.02°) and Cu- K α radiation having wavelengths of K α 1  = 1.54060 Å, K α 2  = 1.54439 Å (Bruker Advance D8, Germany). Morphological characterization was accomplished by scanning electron microscopy (ZEISS EVO 18, UK). The optical properties were determined through UV–vis spectroscopy (SHIMADZU UV/Vis-1650 PC, Japan) into a range of 200–800 nm.

2.5. Antibacterial analysis of ZnO NPs

Escherichia coli bacteria were mainly involved in the determination of the antibacterial performance of ZnO NPs. Initially, the bacteria was stock-cultured in brain heart infusion (BHI) growth medium at −20 °C. Around 3 ml of BHI broth was added to 300 ml of stock-culture and preserved the culture overnight at 36 °C ± 1 °C for 24 h. After 24 h of incubation, dilution of the bacterial suspension (inoculum) was accomplished by using sterile saline. To indicate the bacterial growth during the test, a solution of 2-(4-iodophenyl)−3-(4-nitrophenyl)−5-phenyltetrazolium chloride (INT) in ethanol was added to the bacterial inoculum. Then the inoculum was distributed on a Mueller Hinton Agar Petri Dish in a consistent manner. After that, ZnO A NPs and ZnO B NPs were placed into the wells (prepared by cutting the agar gel) and the systems were preserved at 36 °C ± 1 °C for 24 h to allow successive incubation. After 24 h, the growth of bacteria was monitored and finally, the zone of inhibition for bacterial growth was determined in mm scale.

2.6. Photocatalytic analysis of ZnO NPs

The photocatalytic analysis was performed by monitoring the degradation of Methylene Blue (MB) dye due to ZnO NPs under the influence of UV radiation (having intensity ∼120 μ W cm −2 and wavelength ∼300–400 nm). At first, 5 gm NPs were added into MB solution and mixed properly. The mixture was placed in the dark for 2 h and then irradiated with UV rays with subsequent stirring action and at a variation of time (0, 40, 80, 120, 160, 200 min). The absorbance of the mixture was measured by UV–vis spectroscopy (SHIMADZU UV/Vis-1650 PC, Japan). The efficiency of photodegradation was measured by the following equation:

Where C 0 is the absorption of MB solution before the addition of ZnO NPs and C 1 is the absorption of the mixture solution with respect to time t.

ESR (electron spin resonance) analysis was performed using the EPR spectrometer (Bruker EMX MicroX, Germany) for the identification of the major factor that provides effective photocatalytic performance. During this characterization, DMPO (5,5-dimethyl-1-pyrroline-N-oxide) was used as a spin-trapped reagent in methanol and aqueous state. Moreover, the analysis was performed both in the presence and absence of light irradiation.

3. Results and discussion

3.1. effect analysis of neem leaf extract.

Neem leaf extract contains various phytochemicals such as flavones, quinines, organic acids, aldehyde and ketones which act as reducing agents and significantly reduces the particle sizes. After the successive reduction of particle sizes, the NPs are also affected by the terpenoids. Because of the interaction between the terpenoids and the ZnO NPs become stabilized as terpenoids are effective capping and stabilizing agents. The corresponding mechanism is graphically abstracted into figure 2 . Moreover, the possible seven types of terpenoids that are present in Neem leaf extract are stereotyped in figure 3 .

Figure 2.  Schematic representation of the mechanism of size reduction and stabilization of ZnO NPs during the biosynthesis fabrication scheme using Neem leaf extract.

Figure 3.  Chemical structures of different types of terpenoids subsisting in the Neem leaf extract.

3.2. X-ray diffraction analysis

Figure 4 represents the corresponding X-ray diffraction patterns of ZnO nanoparticles synthesized by sol-gel and bio-synthesis schemes respectively. The intense peaks at the crystal faces (100), (002), (101), (102), (110) assure the emergence of hexagonal wurtzite structure (as shown in figure 5 ) which belong to the space group of P6 3mc (JCPDS card no. 36-1451) [ 18 ]. The bio-synthesized ZnO nano-particles show more acute diffraction peak value introducing the appearance of the high percentage of crystalline phases. In addition, no impurity phases are present in the samples.

Figure 4.  XRD patterns of ZnO A and ZnO B NPs.

Figure 5.  Schematic wurtzite crystal structure of ZnO NPs.

However, considering the most severe diffraction peak (101), the crystallite size (D) can be calculated in accordance with the Debye Scherer formula [ 19 ]:

Hither, β is the Full Width at Half Maxima of the corresponding peak, k is a dimensionless shape factor (∼0.94), while λ is the wavelength of Cu K α radiation (1.54 Å) and ϴ is the Bragg angle. D is mainly the mean size of the ordered domains which is considered to be equal to the particle size (applicable for only particles less than 100 nm). So, the average particle size of ZnO A NPs and ZnO B NPs is 33.20 nm and 25.95 nm respectively [ 19 ]. Again, there remains an inverse relationship between the β and the D which means that narrower peaks are resulted due to larger particles while broader particles are obtained because of smaller particles. The ZnO NPs showed a good agreement with this statement.

Since the crystallite size can be further employed for the determination of defect concentration within the specimen which is designated as the dislocation density ( δ ) and the leading formulae is adopted for this purpose [ 20 ]:

From the exploration of diffraction data, the lattice constant (a & c), inter-planar spacing (d) and unit cell volume (V) of the specimens (table 1 ) can also be enumerated by utilizing the following formulas respectively [ 21 ]:

Where, h, k, l belong to Miller indices.

Table 1.   Structural information on ZnO A and ZnO B NPs.

Besides, the lengthening of the stricture (L) between Zn and O can be enumerated by the following equation [ 20 ]:

Where u corresponds to parameterized constant belonging to wurtzite structure and can be expressed as:

In accordance with the Williamson-Hall proposition, the lattice strain was calculated by adopting the undermentioned equation [ 20 ]:

Figure 6.  W-H plot of (a) ZnO A NPs and (b) ZnO B NPs for the measurement of lattice strain.

3.3. Morphological analysis

Figures 7 (a) and (b) shows the scanning electron micrographs of ZnO A and ZnO B NPs respectively. From the previous section, we have learned that the average particle size of ZnO B NPs (25.97 nm) is smaller than that of ZnO A NPs (33.20 nm). This can be also caused due to the presence of terpenoids in the Neem leaf extract. The terpenoid act not only as a stabilizing agent but also as a powerful reducing agent that interacts with ZnO NPs and reduces its size significantly [ 8 , 17 ]. Moreover, the maximum particles of ZnO A NPs remain between the range of 15 nm to 68 nm, whereas for ZnO B NPs the range lies from 10 nm to 70 nm.

Figure 7.  SEM micrographs of (a) ZnO A NPs and (b) ZnO B NPs.

3.4. Antibacterial activity

Antibacterial activity of ZnO A NPs and ZnO B NPs was analyzed by adopting the agar well diffusion method using Escherichia coli O157: H7 as the bacterial medium. Generally, there involve three mechanisms behind the interaction between the bacteria and the NPs. The first one involves the formation of extremely active hydroxyls and the second one involves the deposition of NPs on the bacteria surface. In addition, for the last one, the NPs accumulates in the cytoplasm or in the periplasmic region of bacteria cell which disrupts the cellular operations and simultaneously disorganizes the membrane. However, in consideration of E. coli , ZnO NPs firstly disorganize the membrane of E. coli and enters into the cytoplasmic region. Positioning themselves into the cytoplasm, the NPs neutralizes the respiratory enzymes and increases the emersion of cytoplasmic contents into the outward direction which impairs the membrane and finally kills the E. coli bacteria resulting in a zone of inhibition of bacterial growth around itself [ 3 , 23 ].

From figure 8 , it is observed that the zone of inhibition of bacterial growth due to ZnO A NPs is different from the zone of inhibition that is caused by ZnO B NPs. However, ZnO B NPs introduce a higher zone of inhibition than ZnO A nanoparticles and the measurements of the inhibition zone of bacterial growth are tabulated in table 2 . According to Krishna R Rangupathi, the antibacterial activity of nanoparticles is a size-dependent property and the property enhances with the reduction of particle size [ 23 ]. As the ZnO B NPs have smaller particle size as well as higher surface area, they show more antibacterial potential than that of ZnO A NPs [ 2 ].

Figure 8.  Antibacterial analysis of ZnO NPs showing the zone of inhibition of the growth of Escherichia coli O157: H7.

Table 2.   Antibacterial measurements of ZnO A NPs and ZnO B NPs.

3.5. Photocatalytic activity

Figure 9.  Degradation mechanism of MB dye by ZnO NPs under the influence of UV irradiation.

However, the corresponding reactions in the photodegradation scheme can be summarized as below [ 24 , 25 ]:

Figure 11 displays the discoloration of MB dye due to the photocatalytic action of ZnO NPs at different times (0, 40 and 120 min). However, figures 12 (a) and (b) illustrates the absorption spectra of MB dye as a function of wavelength under the influence of UV radiation at a variation of time i.e. 0, 40, 80, 120, 160, 200 min. From the graph, it is observed that the absorption rate of MB containing ZnO B NPs decreases more rapidly than that of ZnO A NPs. Moreover, the degradation efficiency ( η ) of ZnO NPs (biosynthesized and sol-gel synthesized) with respect to time is illustrated in figure 13 . The degradation of MB for sol-gel synthesized ZnO are 35.3%, 45.7%, 56.1% 62.4%, 68.9% at 40, 80, 120, 160 and 200 min respectively. Again, the values for biosynthesized ZnO are 36.9%, 47.5%, 62.7%, 72.1%, and 80.2% at 40, 80, 120, 160 and 200 min respectively. So, MB dye degraded more rapidly in the presence of ZnO B NPs backing the reason for smaller particle sizes than that of ZnO A NPs. As the particles become smaller, the active surface area for the photocatalysis increased which results in enhanced degradation of MB [ 26 ]. Moreover, there remain terpenoids in the neem leaf extract which stabilizes the nanoparticles by capping themselves which also causes in the increment of photocatalytic action [ 27 ].

Figure 11.  Visual inspection of the degradation phenomenon of MB dye by ZnO NPs.

Figure 12.  Absorption spectrum of (a) ZnO A NPs and (b) ZnO B NPs as a function of wavelength at 0, 40, 80, 120, 160, 200 min.

Figure 13.  The degradation efficiency of ZnO NPs for methylene blue dye with respect to time.

3.6. Optical analysis

Figures 14 (a) and (b) displays the room temperature absorption spectrum of ZnO nanoparticles fabricated by sol-gel and biosynthesis methods correspondingly. Here, the absorption wavelengths are remaining within the maximum allowable limit of the absorption band of bulk ZnO (∼373 nm). Although the absorption slightly increases up to a wavelength of 363 nm for ZnO A NPs, the maximum incremental value for ZnO B NPs is 356 nm. The slight shift of the absorption peak may be caused due to the variation of particle size and their configuration [ 28 ]. However, this phenomenon results in the presence of a wide range of particle size distribution of ZnO [ 29 ]. Moreover, the redshift of ZnO A NPs compared to ZnO B NPs corresponds to the formation of agglomeration in the specimens significantly. Furthermore, in accordance with Gunanlan Sangeetha et al the shifting of absorption band to the higher wavelength as well as higher energy was associated with the increment of the size of nanoparticles [ 30 ]. Moreover, considering the direct interband transition between the valence band and the conduction band, the absorption band gap energy was measured by adopting the following Tauc's formula [ 31 ]:

Where A is an energy-independent constant, α is the absorption coefficient, h υ is for the photon energy, and E g is the optical band gap energy. The E g of the ZnO NPs was obtained from the ( α h υ ) 2 versus h υ plot (as shown in the inset of figures 14 (a) and (b). Where the extrapolation of the linear segment of the graph to (α h υ ) 2  = 0 provides the value of E g for ZnO NPs. It is observed that the optical band gap energy of ZnO B NPs (3.25 eV) is higher than that of ZnO A NPs (3.23 eV). This incremental phenomenon is mainly attributed to the quantum confinement effect. According to this theory, as the particle size decreases, the electrons in the valence band and the holes in the conduction band confine themselves within a space having a dimension of the de Broglie wavelength. However, this confinement influences the quantization of the energy and the momentum of the corresponding carriers and also enhances the optical transition energy between the valence band and the conduction band resulting in a broad band gap [ 32 ].

Figure 14.  Absorption spectra of (a) ZnO A NPs and (b) ZnO B NPs (inset shows ( α h υ ) 2 versus h υ plot for the determination of band gap energy.

Figure 15 displays the UV visible transmittance spectrum of ZnO A NPs and ZnO B NPs. Here, the transparency of ZnO B NPs is greater than that of ZnO due to the reduced particle size of ZnO B NPs. From the research of Takuya Tsuzuki, it is clear that smaller particles are capable to show higher transparency at the visible range of spectrum [ 33 ]. However, the UV blocking characteristics are almost similar for each of the variants of NPs.

Figure 15.  Typical transmittance spectra of ZnO NPs.

4. Conclusion

In summary, ZnO NPs were synthesized by two different methods i.e., sol-gel and biosynthesis method. The green synthesis of ZnO NPs allows avoiding the toxic chemical agents that are used in the sol-gel method for the size reduction. However, the Neem leaf extract possesses some phytochemicals which not only performs in the reduction of the particle sizes but also provide sufficient stabilization. Although, the average particle size of ZnO B NPs (25.97 nm) was smaller than that of ZnO A NPs (33.20 nm), the optical band gap energy of ZnO B NPs was higher than that of ZnO A NPs due to the quantum confinement effect. In addition, the antibacterial and photocatalytic properties of ZnO B NPs were greater than that of ZnO A NPs. Where, the zone of inhibition of bacterial growth for ZnO B NPs was 14.5 mm and for ZnO A NPs, it was 9.3 mm. Moreover, the degradation efficiency of ZnO B NPs at 200 min was 80% while for ZnO A NPs, the corresponding efficiency was 68%. Again, from the ESR analysis, it was proved that the OH · radicals were the main contributing factor for the degradation of MB dye. So, based on the comparison between the properties of the two variants, it is concluded that the biosynthesis method shows more effectiveness than the sol-gel method for the synthesis of ZnO NPs.

Acknowledgments

The authors are grateful to Rajshahi University of Engineering & Technology (RUET) for providing the opportunity to perform various tests. Special thanks go to Tasmia Zaman, Assistant Professor, Department of Glass & Ceramic Engineering, Rajshahi University of Engineering & Technology, Bangladesh for her cordial assistance.

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Polymer Chemistry

In situ pet-raft polymerization to prepare guanidine-and-carbohydrate modified zno nanoparticles †.

* Corresponding authors

a State and Local Joint Engineering Laboratory for Novel Functional Polymeric Materials, College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou, China E-mail: [email protected]

b Center for Soft Condensed Matter Physics and Interdisciplinary Research & School of Physical Science and Technology, Soochow University, Suzhou, China E-mail: [email protected]

ZnO–polymer core–shell nanoparticles were successfully prepared using a simple in situ open-to-air PET-RAFT method. The utilization of vinyltriethoxysilane (VTES) modified ZnO NPs as catalysts for polymerization, along with the grafting of polymers onto the ZnO NPs, offers significant antibacterial properties. The cationic monomer methacrylamide guanidine hydrochloride (MAGH) and the glycomonomer 2-methacrylamido glucopyranose (MAG) were grafted onto the ZnO NPs surface, further enhancing the antibacterial properties by promoting contact with bacteria and specific recognition of E. coli FimH proteins, leading to a significant improvement in the antibacterial ability compared with ZnO NPs. By combining the photocatalytic and antibacterial properties of ZnO NPs, the preparation of a core–shell material with good antibacterial properties was successfully achieved, providing a new strategy for the synthesis of antimicrobial materials.

• This article is part of the themed collection: Polymer Chemistry 15th Anniversary Collection

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In situ PET-RAFT polymerization to prepare guanidine-and-carbohydrate modified ZnO nanoparticles

J. Zhao, Y. Rao, H. Zhang, Z. Zhu, L. Yao, G. Chen and H. Chen, Polym. Chem. , 2024, Advance Article , DOI: 10.1039/D4PY00223G

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• Published: 30 August 2023

ZnO doped C: Facile synthesis, characterization and photocatalytic degradation of dyes

• Nasser Mohammed Hosny 1 ,
• Islam Gomaa 1 , 2 ,
• Maryam G. Elmahgary 3 , 4 &
• Medhat A. Ibrahim 5 , 6  

Scientific Reports volume  13 , Article number:  14173 ( 2023 ) Cite this article

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Carbon doped ZnO nanoparticles have been synthesized from the thermal decomposition of Zinc citrate precursor. The precursor was synthesized from semi-solid paste and then subjected to calcination at 700 °C to produce ZnO nanoparticles. The precursor and ZnO were characterized by Fourier Transform Infrared Spectroscopy, UV–visible (UV–Vis) spectra, Transmission Electron Microscope, Field Emission Scanning Electron Microscope, Energy Dispersive Analysis by X-ray (EDAX), X-ray powder diffraction (XRD), and X-ray photoelectron spectroscopy (XPS). The results ensured the formation of hexagonal 2D-ZnO nanoparticles with a layer thickness of 25 nm. The optical band gap of ZnO was determined and found to be 2.9 eV, which is lower than the bulk. Photocatalytic degradation of Fluorescein dye as an anionic dye and Rhodamine B as a cationic dye was evaluated via C-ZnO NPs under UV irradiation. ZnO displayed 99% degradation of Fluorescein dye after 240 min and a complete photocatalytic degradation of Rhodamine B dye after 120 min under UV irradiation.

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Introduction.

The discharge of industrial wastewater contaminated with organic dyes resulted from the processing of fabrics, pharmaceutics, cosmetics, and others, has become the main cause of excessive water contamination 1 . The exposure of dyes even in a small concentration can critically influence the water quality of the aquatic environment 2 . Dyes as Rhodamine B, and methylene blue are non-biodegradable, toxic and carcinogenic hazardous dyes 3 , 4 . Fluorescein is a highly fluorescent dye that can be used to visualize the structure of materials and track the flow of fluids and stable over a wide range of pH and temperature conditions 5 . Non-biodegradable and resistant dyes represent a big problem because they can persist in the environment for long periods of time, where they can have many of negative environmental impacts 6 . It need multiple processes, such as adsorption 7 , filtration 8 , and photocatalysis 9 , for efficient purification of water. Photo catalysis is considered an eco-friendly sustainable technique for the removal of dyes from wastewater 10 , 11 . Photo catalysis is a promising approach for future techniques that rely on a renewable available and an inexpensive natural sunlight radiations 12 , 13 . Nanostructure defects are critical in defining the properties and performance of nanostructures in the targeted applications 14 . Without enforced parameter like pH and Temperature few of photocatlysts have an efficient degradation impact of both anionic and cationic dyes 15 , 16 . Two-dimensional materials are sheet-like nanomaterials that are made of thin multiple layers with a thickness of several nanometers 17 , 18 . Nano-diameter materials have attracted increasing attention for photocatalytic applications over other morphologies because of their unique thickness and their doubly exposed active surface, peculiar nature of the electronic density of state spectrum 19 . The photocatalytic reactions depend on induction by UV–visible light lies on a surface of a semiconductor such as ZnO 20 . It is an excellent n-type semi-conductor with band gap energy (3.3 eV) it has unique characteristics as high photosensitivity, good physical and chemical stability and high electron mobility 17 , 21 , 22 . ZnO has significant potential as a powerful antibacterial agent and high safety profile that might eventually replace antibiotics 23 . These characteristic properties enabled ZnO to be a promising material for a variety of applications, as solar cells, photo-catalysis and gas sensor 24 .Metallic 25 and non-Metallic (e.g. Carbon) 26 doping has a significant impact on band gap engineering and photo-catalysis efficiency 27 , 28 . The enhancement of photocatalytic efficiency for ZnO-carbon doped might be due to the good dye adsorption capacity, direct photo-oxidation of dye, and inhibition of photo-induced electron–hole recombination 29 . Doping synthesis usually need sophisticated methods lacking simplicity and high yield production 30 , 31 . Solid state synthesis of metal oxides from molecular precursor have several advantages over the other synthetic approaches as it is simple, gives good yields that facilitates large scale 32 .The use of ZnO as a photo-catalyst was studied in the degradation of Rhodamine B dye under UV radiation 33 , 34 , 35 . The effect of catalyst dose and particle size on the degradation efficiency of the dyes was studied 36 . In continuation to our previous work in synthesis and hybridization of metal oxides investigation and apply them as efficient materials in water treatment 37 , 38 , 39 , 40 , 41 , 42 . ZnO mixed with ZnC were synthesized by benign solid state technique from citrate molecular precursor. Various techniques were used in characterization of the calcination products. The photocatalytic activity of the synthesized ZnO/ZnC mixture showed efficient photocatalytic activity in degradation of various dyes in comparison with other catalysts.

Experimental

Materials and methods.

Zinc acetate dihydrate (Zn(CH 3 COO) 2 ·2H 2 O ≥ 99%,Acros) and citric acid anhydrous (C 6 H 8 O ≥ 99.5%, Fisher scientific), Dyes: Rhodamine B ≥ 95% (HPLC), Merck) and Fluorescein sodium salt ≥ 97.5% zHPLC),Merck).The solvent used is deionized (DI) Milli-Q water. The UV–Vis absorption spectra of the prepared samples was measured using a double beam spectrophotometer (Cary 5000 UV–Vis-NIR, Agilent Technologies). The FTIR spectra were collected using a FTIR spectrometer (Vertex 70, Bruker, Germany). XRD of the as-prepared Zinc-Citrate precursor and ZnO samples were characterized using a Malvern Panalytical Empyrean 3 diffractometer. The morphology and particle size of the samples were determined by FESEM, (Quattro S, Thermo Scientific).

Synthesis of zinc citrate precursor and ZnO nanoparticles (NPs)

The precursor was prepared by semisolid method 41 in which, of Zn(CH 3 COO) 2 ·2H 2 O and citric acid in (1:1), (1:2) and (1:3) molar ratio were grinded well in a mortar till a very fine mixture was obtained. Then 1 mL of Milli-Q-water was added with continuous grinding till a homogenous paste was formed. The paste was dried at 100 °C for 3 h. The calcination temperature has been determined from TGA of the precursor Fig. S1 . Previous reports 43 indicated the formation of sheets of ZnO when the precursor was calcined at 700 °C, which is important in photo-catalysis. In addition, the powder obtained from (1:2) molar ratio was calcined in air at 400, 500, 600 and 700 °C for 2 h at atmospheric pressure to investigate the impact of temperature on particle shape in Fig. S1 (400–600).

Anal. Found for Zn(C 6 H 7 O 7 )0.2H 2 O C , 24.0; H , 3.9; Zn , 23.3%. Calc.: C , 24.7; H , 3.7; Zn , 22.4%

Photo-catalysis

To evaluate the photocatalytic activity of the synthesized C-ZnO, Rhodamine B (RB) and Flurocine (Flu) were utilized as models for resistant cationic and anionic organic water pollutants. The stock dye solution concentrations for RB and Flu were 5 × 10 –5 and 6 × 10 –5  M, respectively. A batch reactor containing the proper amount of photo catalyst (0.1 g) and the investigated dye solution (100 mL) was ultrasonically agitated for 60 s to ensure photo catalyst dispersion, and the suspension was magnetically stirred in the dark at 500 rpm for 60 min to ensure adsorption–desorption equilibrium. Then, the photo degradation tests were conducted using a 15 W Sylvania UV-A lamp for UV-A irradiation (wavelength 315–400 nm); the batch reactor was irradiated for 120 min with continuous stirring at 500 rpm; 5 mL-aliquots were pipetted out every 30 min during the irradiation process; and the aliquots were centrifuged for 30 min at 3300 rpm. The UV–Vis absorbance spectra of the filtrates were analyzed using a Thermoscientific Evolution 300 UV–Vis spectrophotometer, allowing the dye removal percentage to be calculated using Eq. (1):

where A o and A t are the absorbance of the investigated dye (RB or Flu) at λmax (554 nm for RB and 490 nm for Flu) in the dark and at a time (t) of irradiation, respectively.

Results and discussions

Synthesis of the precursor and zno-nps.

Optimized molar ratio (1:2) of Zn(OAc) 2 .2H 2 O : citric acid (CA) to form main precursor to achieve the thinnest thickness of Nano-sheets according to past reports 43 , 44 for photo catalysis applications. Prepared from the reaction of Zn(OAc) 2 .2H 2 O with citric acid (CA), it resulted [Zn(CA)0.2H 2 O] in a 1:1 molar ratio, and a residual of citric acid may remain unbound. FESEM of the precursor Fig. S2 A. Indicates that, the precursor is a flakes of crystalline materials and some irregular granules. EDX indicates that the precursors include both Zn, C and O. The disappearance of any other elements confirms the purity of the precursor. The mapping of Zn, O, and C atoms indicates that the atoms are regularly distributed, and Zn atoms are surrounded by oxygen atoms as indicated from the magnified image of the mapping of the total distribution of elements and EDX analysis Fig. S2 B–F. After Calcination at 700 °C for three precursors, the elemental analysis ratio obtained from Energy Dispersive X-Ray Analysis (EDX) indicated that the average of carbon weight percentage content in ZnO-nanoparticles obviously increased from 21.57, 34.5 and 40.9 for (1:1), (1:2) and (1:3). Figure S3 (1:1) and Fig. S3 (1:3) for (1:1) and (1:3) ratio respectively.

Characterization of the precursor

IR spectra of the precursor Fig. S4 was compared carefully with that of the free citric acid to deduce the mode of chelation of citric acid. Citric acid has three carboxyl groups; two of them (1 and 2) are symmetric, so the spectrum of the citric acid exhibits two bands at 3494 and 3292 cm −1 due to ν(OH) of the three carboxyl groups. Another shoulder band is observed at 3224 cm −1 owing to the free (OH). In addition to that, two strong bands are observed at 1735 and 1703 owing to ν as (COOH) of the protonated three carboxyl groups 37 . In the spectra of the precursor, two bands are observed at 3468 and 3382 cm −1 owing to two ν(OH) of the two carboxyl groups (1 and 3), while the band of the free (OH) group has disappeared. It is worth noting that the shoulder at 3492 cm −1 due to the presence of unreacted citric acid. Two strong bands are also observed, including a strong band at 1702 cm −1 in its position as in the free acid due to the starching vibrations ν as (COOH) of the protonated carboxyl group (3). The second band at 1628 cm −1 is attributed to ν as (COO-) of the deprotonated carboxyl group (1) 37 , 38 , 39 This band is shifted to a lower wave number as a result of the coordination of this group with the Zn(II) ion. The difference between the asymmetric and symmetric groups that lies at 1443 cm −1 is 180 cm −1 indicating the monodentate nature of this group. The broad band at 3584 cm −1 is attributed to a coordinated water molecule. Two weak bands are observed at 510 and 525 cm −1 owing to Zn–O band 40 . From the above findings, it is suggested that CA chelates Zn(II) as indicated in Fig. S5 .

Figure S6 . Precursor XRD pattern shows peaks at 2θ = 11.0, 13.5, 15.8, 21.8, 26.5, 31.1° confirming the crystallinity nature of the precursors. The peaks assigned with asterisk point to crystalline citric acid the presence of these peaks point to unreacted citric acid.

Characterization of the calcination products

Xrd and xps.

XRD diffraction pattern of the product resulted from the calcination of the precursor Fig.  1 . indicates diffraction peaks at 2θ = 31.9, 34.5, 36.4, 47.6, 56.7, 62.9, 66.4, 68.1, 69.2, 72.6 and 77.1o corresponds to the planes (100), (002), (101), (102), (110), (103), (200), (112), (201), (004) and (202). These peaks is well indexed to C-ZnO (JCPDS card NO. 01–075- 0576) with hexagonal structure, space group p63mc and lattice parameters a = b = 3.24 Å, c = 5.19 Å, α = β = 90° and ɣ = 120°.The determined crystallite size from the major peak at 36.4224 from Debye-Scherer relation 45 : D = 0.94 λ/β cosθ is 75 nm.

XRD pattern of ZnO nanoparticles.

The careful observation of the XRD pattern indicates that the doped C has shifted the plane (101) to a higher 2θ, which leads to deformation in the unit cell 42 . The calculated crystallite size, lattice parameters, and unit cell volume of ZnO have changed in comparison with pure ZnO due to the change in the d-spacing tabulated in Table S1 42 , 43 , 44 . The C-doping effects on the reduction of the cell volume and the difference in the lattice parameters of C-ZnO can be attributed to the structure defects (O vac ) caused by C-doping. The occupation of O vac by the carbon anion with a radius (69–76 pm), which is higher than that of oxgen (57–66 pm), will lead to a disturbance in the lattice volume and parameters of ZnO. Also, due to the charge of both carbon and oxygen, the substitution of O(–II) by C(–IV) will unbalance the charge of the system, which requires oxygen loss to remain balanced. The results agree with previous research where C-doping-induced unit cell changes were also observed 45 . The presence of carbon was supported by the carbon weight ratio in XPS and EDAX results.

Additionally, XPS was done to ensure the chemical composition of the tow dimentional C-ZnO surface. XPS survey spectra of Zn 2p and O 1 s of C-ZnO nanoparticles are shown, respectively, in Fig.  2 A–D. The binding energies are calibrated considering the C 1 s emission centered at 284.5 eV. The C 1 s spectrum of doped ZnO can be deconvoluted into two components at 286.1, 287.6 and 289.7 eV. The atomic ratio of Zn, O, and C were 58.43, 38.61 and 2.96%, respectively. Zn 2p spectrum displays two main peaks of Zn 2p 1/2  and Zn 2p 3/2  states centered at 1022.64 eV and 1045.79 eV, respectively. These peaks confirm the presence of Zn atom in lattice of ZnO crystal 46. The difference in binding energies between the peak of Zn 2p 3/2 and that of Zn 2P 1/2 is 23.15 eV; that is the characteristic for C-ZnO. The peak profile of the O 1 s state exhibits a broad band that extends from 530 to 534 eV. The deconvusion of this peak exhibits two peaks: the first at 531.38 eV is attributed to lattice oxygen (Atomic % 64.26), and the second peak at 533.0 eV is owing to surface oxygen atoms (Atomic % 35.74) 23 . XPS indicates that the carbon composition is relatively high (34%), which may arise from the incomplete combustion of the precursor.

XPS of ZnO nanoparticles ( A ) Zn 2p spectrum ( B ) C 1 s specturm ( C ) O 1 s spectrum ( D ) XPS survey spectrum of ZnO nanoparticles.

FT-IR and UV–visible spectra

The formation of ZnO after calcinations of the precursor was further supported by IR and UV spectra. The IR spectrum of ZnO Fig.  3 shows bands at 415, 448, 517, and 612 cm −1 , these bands are characteristic for ZnO nanoparticles 17 .Also, UV- spectrum Fig.  4 shows a characteristic band at 385 nm of C-ZnO that can be attributed to the intrinsic band-gap absorption of ZnO 46 .

IR spectrum of ZnO NPs.

UV spectrum of ZnO NPs.

FESEM images Fig.  5 show aggregates of granules and irregular sheets with average particle size 33 nm and average thickness 25 nm Fig.  6 . These crystalline sheets are arranged in layers. The mapping of ZnO nanoparticles Fig.  7 indicates that oxygen is regularly distributed around Zn atoms.

FESEM of ZnO NPs with different magnifications.

Particle thickness distribution.

EDS for total element’s distribution. ( a ) Elemental mapping in total distribution of Zinc, Carbon and Oxygen elements, ( b ) Zn mapping, ( c ) Oxygen mapping and ( d ) Carbon mapping.

Figure  8 displays the ZnO HR-TEM images and SAED. The SEM results are supported by the TEM images of ZnO, which show that the particles are virtually hexagonal with just a small thickness fluctuation. According to the histogram in Fig.  9 , the range of particle sizes was 20–140 nm within an average of 73 nm. According to these images, the majority of ZnO NPs have hexagonal shapes and have an average particle size of 100 nm. The SAED pattern shows that the synthesized ZnO's diffraction rings displayed Debye–Scherrer rings with the designations (010), (002), (011), (012), (110), and (103), respectively. The TEM analysis estimates of particle size are comparable to the XRD analysis estimates; moreover, selected area electron diffraction (SAED) appears to be a good argument as a simple and convenient method for characterizing the macroscopic structures of 2D materials, and the instrument we constructed allows the study of the weak interaction with 2D materials 48 . SAED pattern of 2D material nature, which cannot show any high-order Laue zones since there are few layers in the beam direction. In comparison to HOLZ rings regarding 3D shape 49 which obviously illuminated herenin and revealed layered 2D materials with low symmetry, 2D materials have emerged as anisotropic electronic and optoelectronic candidates.

HR-TEM images at different magnification of ZnO NPs and SAED pattern.

Histogram of particle size distribution.

Optical properties

For the purpose of displaying the absorption profile and optical characteristics of the nanoparticles, DRS is a necessary technique. The absorption-band-edge of ZnO nanoparticles is seen at 100 nm in Fig.  10 A, which corresponds to a band gap energy of 2.9 eV (Tauc plot), in Fig.  10 B The reduction of the optical band gap in comparison with the commercial (3.7 eV) may come from the resulted carbon from the incomplete combustion of the precursor 47 , 48 , 49 . The synthesised ZnO shows a shift in wavelength and a decrease in band gap, boosting its catalytic activity to the visible range Fig.  10 .

( A ) UV–Vis diffuse reflectance spectrum and ( B ) Tauc plot of ZnO NPs.

Photocatalytic activity

The photocatalytic activities of the synthesized ZnO NPs were evaluated via the photodegradation of both anionic and cationic dyes under UV irradiation. Fluorescein dye was used as a type of anionic dye, while Rhodamine B was the cationic dye. Prior to illumination, 100 mg of photocatalyst was added to the dye aqueous solution (100 mL, 10 ppm). The solution was stirred in the dark for 60 min in order to achieve absorption–desorption equilibrium, then the photocatalytic reaction was started. The photocatalyst will then be exposed to UV irradiations for the desired time.

Although bulk ZnO has barely low photocatalytic reactivity under UV irradiations due to the rapid recombination of the charge carriers and the wide band gap energy, it displays 99% degradation of Fluorescein dye after 240 min, as shown in Fig.  11 .

UV–visible spectra of Flu dye solution irradiated with UV light at different time intervals in presence of C doped ZnO photocatalyst.

Also, Fig.  12 displays the perfect photocatalytic behavior of prepared ZnO toward the photodegradation of Rhodamine B dye under UV irradiation sources; nearly complete decolorization was accomplished after only 120 min., of UV-A irradiations. And this give superiority of C-ZnO in Comparison over the photocatalytic activities of different ZnO doped catalysts toward the photo-degradation of RB in Table 1 .

UV–visible spectra of RhB dye solution irradiated with UV light at different time intervals in presence of C doped ZnO photocatalyst.

To investigate the role of reactive species in the degradation of RhB and Flu dyes, trapping experiments were done using ammonium oxalates, isopropanol, benzoquinone, and silver nitrate over a ZnO catalyst. The objective was to comprehend the roles played by positive holes, hydroxyl radicals, superoxide radicals, and the electron conduction band in the photodegradation process. It was observed that the addition of silver nitrate (AgNO 3 ) had no effect on the efficiency of photodegradation, indicating that electron conduction has no effect on the removal of both dyes Fig.  13 . The presence of benzoquinone, ammonium oxalate, and isopropanol had a significant effect on the photocatalytic performance of carbon-doped ZnO, indicating that hydroxyl radicals, positive holes, and superoxide radicals are involved in the degradation of RhD and Flu dyes. Regarding Flu dye, it is clear that superoxide radicals play the dominant role in the photodegradation process.

Effect of various scavengers over carbon-doped ZnO.

Moreover, the high stability of the ZnO catalyst was demonstrated by the successful removal of RhB and Flu dyes even after five consecutive cycles Fig.  14 indicating that the prepared ZnO is extremely stable.

Cycling experiments of carbon-doped ZnO for RhB and Flu dye degradation under UV light irradiation.

Mechanism of photocatalysis

The mechanism for photocatalytic degradation of the used dyes onto ZnO nanoparticles by UV irradiation suggests the transfer of the electrons that exist in the valence band of ZnO to the conduction band under the effect of UV radiations. The absorbed energy should be higher than the current energy band gap of ZnO NPs (3.0 eV). The absorbed radiation will promote the electrons (e − ) to the conduction band and holes (h + ) in the valance band. The generated holes can oxidize the dyes directly or react with H2O generating hydroxyl radicals (·OH). On the other hand, the photoelectrons in the conduction band can reduce the adsorbed O2 on the surface of C-ZnO into superoxide radical (O 2− ). Both OH and·O 2– can decompose the dyes 56 , 57 .

The suggested mechanism can be represented as follow:

ZnO nanoparticles have been synthesized by a simple solid state decomposition method. The used technique has advantageous as it is simple benign and provide high yield of 2D-carbon doped ZnO nanoparticles. The obtained ZnO have high photocatalytic activity in decomposing both cationic and anionic harmful azo dyes. The current work can be applied to synthesize other carbon doped metal oxides in two-dimensional scale that can be applied as catalysts in degrading and treatment of industrial water from harmful dyes.

Data availability

Data will be made available on request in contact to Prof.Medhat through ([email protected]).

Hosny, N. M., Gomaa, I. & Elmahgary, M. G. Adsorption of polluted dyes from water by transition metal oxides: A review. Appl. Surf. Sci. Adv. 15 , 100395 (2023).

Google Scholar  

Warren-Vega, W. M., Campos-Rodríguez, A., Zárate-Guzmán, A. I. & Romero-Cano, L. A. A current review of water pollutants in American continent: Trends and perspectives in detection, health risks, and treatment technologies. Int. J. Environ. Res. Public Health 20 , 4499 (2023).

CAS   PubMed   PubMed Central   Google Scholar  

Morsy, M. et al. Highly efficient photocatalysts for methylene blue degradation based on a platform of deposited GO-ZnO nanoparticles on polyurethane foam. Molecules 28 , 108 (2022).

PubMed   PubMed Central   Google Scholar  

Fatimah, I., Purwiandono, G., Hidayat, A., Sagadevan, S. & Kamari, A. Mechanistic insight into the adsorption and photocatalytic activity of a magnetically separable γ-Fe 2 O 3 /Montmorillonite nanocomposite for rhodamine B removal. Chem. Phys. Lett. 792 , 139410 (2022).

CAS   Google Scholar  

Barmin, R. A. et al. Impact of fluorescent dyes on the physicochemical parameters of microbubbles stabilized by albumin-dye complex. Colloids Surfaces A Physicochem. Eng. Asp. 647 , 129095 (2022).

Al-Tohamy, R. et al. A critical review on the treatment of dye-containing wastewater: Ecotoxicological and health concerns of textile dyes and possible remediation approaches for environmental safety. Ecotoxicol. Environ. Saf. 231 , 113160 (2022).

CAS   PubMed   Google Scholar  

Allahkarami, E., Dehghan Monfared, A., Silva, L. F. O. & Dotto, G. L. Toward a mechanistic understanding of adsorption behavior of phenol onto a novel activated carbon composite. Sci. Rep. 13 , 1–16 (2023).

Morsy, M., Abdel-Salam, A. I., Rayan, D. A., Gomaa, I. & Elzwawy, A. Oil/water separation and functionality of smart carbon nanotube–titania nanotube composite. J. Nanoparticle Res. 24 , 1–15 (2022).

Abel Noelson, E. et al. Excellent photocatalytic activity of Ag2O loaded ZnO/NiO nanocomposites in sun-light and their biological applications. Chem. Phys. Lett. 796 , 139566 (2022).

Kowsalya, P., Bharathi, S. U. & Chamundeeswari, M. Photocatalytic treatment of textile effluents by biosynthesized photo-smart catalyst: An eco-friendly and cost-effective approach. Environ. Dev. Sustain. 2023 , 1–21. https://doi.org/10.1007/S10668-023-03172-6 (2023).

Article   Google Scholar  

Sahoo, D. et al. Cost effective liquid phase exfoliation of MoS2 nanosheets and photocatalytic activity for wastewater treatment enforced by visible light. Sci. Rep. 10 , 1–12 (2020).

Mathialagan, A. et al. Fabrication and physicochemical characterization of g-C3N4/ZnO composite with enhanced photocatalytic activity under visible light. Opt. Mater. 100 , 109643 (2020).

Sun, Y. & O’Connell, D. W. Application of visible light active photocatalysis for water contaminants: A review. Water Environ. Res. https://doi.org/10.1002/wer.10781 (2022).

Article   PubMed   PubMed Central   Google Scholar  

Wareppam, B. et al. Variation in defects and properties in composite of ZnO and α-Fe 2 O 3 for sustainable wastewater treatment. J. Appl. Phys. https://doi.org/10.1063/5.0151016 (2023).

Mansor, E. S., El Shall, F. N. & Radwan, E. K. Simultaneous decolorization of anionic and cationic dyes by 3D metal-free easily separable visible light active photocatalyst. Environ. Sci. Pollut. Res. 30 , 10775–10788 (2023).

Groeneveld, I., Kanelli, M., Ariese, F. & van Bommel, M. R. Parameters that affect the photodegradation of dyes and pigments in solution and on substrate: An overview. Dye. Pigment. 210 , 110999 (2023).

Omar, A. et al. Investigation of morphological, structural and electronic transformation of PVDF and ZnO/rGO/PVDF hybrid membranes. Opt. Quantum Electron. 55 , 1–21 (2023).

Chang, Y. M., Lin, H. W., Li, L. J. & Chen, H. Y. Two-dimensional materials as anodes for sodium-ion batteries. Mater. Today Adv. 6 , 100054 (2020).

Luo, B., Liu, G. & Wang, L. Recent advances in 2D materials for photocatalysis. Nanoscale 8 , 6904–6920 (2016).

ADS   CAS   PubMed   Google Scholar  

Samadi, M., Zirak, M., Naseri, A., Khorashadizade, E. & Moshfegh, A. Z. Recent progress on doped ZnO nanostructures for visible-light photocatalysis. Thin Solid Films 605 , 2–19 (2016).

ADS   CAS   Google Scholar  

Mohamed, K. M., Benitto, J. J., Vijaya, J. J. & Bououdina, M. (2023) Recent advances in ZnO-based nanostructures for the photocatalytic degradation of hazardous. Non-Biodegradable Medicines. Cryst. 13 , 329 (2023).

Hegazy, M. A. et al. Effect of CuO and graphene on PTFE microfibers: Experimental and modeling approaches. Polymers 14 , 1–14 (2022).

Siddiqi, K. S., Ur Rahman, A., Tajuddin, & Husen, A. Properties of zinc oxide nanoparticles and their activity against microbes. Nanoscale Res. Lett. 13 , 1–13 (2018).

Mourya, A. K. et al. Tuning the morphologies of ZnO for enhanced photocatalytic activity. Inorg. Chem. Commun. 154 , 110850 (2023).

Pradeev Raj, K., Sadaiyandi, K., Kennedy, A. & Sagadevan, S. Photocatalytic and antibacterial studies of indium-doped ZnO nanoparticles synthesized by co-precipitation technique. J. Mater. Sci. Mater. Electron. 28 , 19025–19037 (2017).

Kumari, V., Mittal, A., Jindal, J., Yadav, S. & Kumar, N. S-, N- and C-doped ZnO as semiconductor photocatalysts: A review. Front. Mater. Sci. 13 , 1–22 (2019).

Bhosale, A., Kadam, J., Gade, T., Sonawane, K. & Garadkar, K. Efficient photodegradation of methyl orange and bactericidal activity of Ag doped ZnO nanoparticles. J. Indian Chem. Soc. 100 , 100920 (2023).

Foo, C. et al. Characterisation of oxygen defects and nitrogen impurities in TiO 2 photocatalysts using variable-temperature X-ray powder diffraction. Nat. Commun. 121 (12), 1–13 (2021).

Babar, S. B. et al. An efficient fabrication of ZnO–carbon nanocomposites with enhanced photocatalytic activity and superior photostability. J. Mater. Sci. Mater. Electron. 30 , 1133–1147 (2019).

Elmanzalawy, M. et al. Mechanistic understanding of microstructure formation during synthesis of metal oxide/carbon nanocomposites. J. Mater. Chem. A https://doi.org/10.1039/D3TA01230A (2023).

Siriwong, C. et al. Doped-metal oxide nanoparticles for use as photocatalysts. Prog. Cryst. Growth Charact. Mater. 58 , 145–163 (2012).

Lu, H., Wright, D. S. & Pike, S. D. The use of mixed-metal single source precursors for the synthesis of complex metal oxides. Chem. Commun. 56 , 854–871 (2020).

Byrappa, K. et al. Photocatalytic degradation of rhodamine B dye using hydrothermally synthesized ZnO. Bull. Mater. Sci. 29 , 433–438 (2006).

Piras, A. et al. Photocatalytic performance of undoped and Al-doped ZnO nanoparticles in the degradation of rhodamine b under UV-visible light: The role of defects and morphology. Int. J. Mol. Sci. 23 , 15459 (2022).

Tuc Altaf, C. et al. Impact on the photocatalytic dye degradation of morphology and annealing-induced defects in zinc oxide nanostructures. ACS Omega 8 , 14952–14964 (2022).

Dodoo-Arhin, D. et al. Photocatalytic degradation of Rhodamine dyes using zinc oxide nanoparticles. Mater. Today Proc. 38 , 809–815 (2021).

Gomaa, I., Abdel-Salam, A. I., Khalid, A. & Soliman, T. S. Fabrication, structural, morphological, and optical features of Mn2O3 polyhedron nano-rods and Mn 2 O 3 /reduced graphene oxide hybrid nanocomposites. Opt. Laser Technol. 161 , 109126 (2023).

Abdel-Salam, A. I., Gomaa, I., Khalid, A. & Soliman, T. S. Investigation of raman spectrum, structural, morphological, and optical features of Fe 2 O 3 and Fe 2 O 3 /reduced graphene oxide hybrid nanocomposites. Phys. Scr. 97 , 125807 (2022).

ADS   Google Scholar  

Hosny, N. M. Synthesis, characterization and optical band gap of NiO nanoparticles derived from anthranilic acid precursors via a thermal decomposition route. Polyhedron 3 , 470–476 (2011).

Hosny, N. M., Hazem, A. & Moalla, S. M. N. Synthesis, characterization and analytical applications of cobalt ferrite nanoparticles. Chem. Data Collect. 42 , 100948 (2022).

Hosny, N. M., Gomaa, I., Abd El-Moemen, A. & Anwar, Z. M. Adsorption of Ponceau Xylidine dye by synthesised Mn2O3 nanoparticles. Int. J. Environ. Anal. Chem. https://doi.org/10.1080/03067319.2021.2014470 (2021).

Hosny, N. M., Gomaa, I., Abd El-Moemen, A. & Anwar, Z. M. Synthesis, magnetic and adsorption of dye onto the surface of NiO nanoparticles. J. Mater. Sci. Mater. Electron. 31 , 8413–8422 (2020).

Yang, Z., Liu, Q. H. & Yang, L. The effects of addition of citric acid on the morphologies of ZnO nanorods. Mater. Res. Bull. 42 , 221–227 (2007).

Cho, S. et al. Precursor effects of citric acid and citrates on ZnO crystal formation. Langmuir 25 , 3825–3831 (2009).

Norrish, K. & Taylor, R. M. Quantitative analysis by X-ray diffraction. Clay Miner. Bull. 5 , 98–109 (1962).

Bai, L. et al. Sunlight-driven photocatalytic degradation of organic dye in wastewater by chemically constructed Zno/Cs4siw12o40 nanoheterojunction. SSRN Electron. J. https://doi.org/10.2139/SSRN.4053254 (2022).

Ma, Z., Ren, F., Ming, X., Long, Y. & Volinsky, A. A. Cu-doped ZnO electronic structure and optical properties studied by first-principles calculations and experiments. Materials 12 , 196 (2019).

ADS   CAS   PubMed   PubMed Central   Google Scholar  

Liu, H. et al. Structural, optical and magnetic properties of Cu and v co-doped ZnO nanoparticles. Phys. E Low-Dimensional Syst. Nanostruct. 47 , 1–5 (2013).

Nafees, M., Liaqut, W., Ali, S. & Shafique, M. A. Synthesis of ZnO/Al:ZnO nanomaterial: Structural and band gap variation in ZnO nanomaterial by Al doping. Appl. Nanosci. 3 , 49–55 (2013).

Nandi, P. & Das, D. ZnO-CuxO heterostructure photocatalyst for efficient dye degradation. J. Phys. Chem. Solids 143 , 109463 (2020).

Pradeev Raj, K. et al. Influence of Mg doping on ZnO nanoparticles for enhanced photocatalytic evaluation and antibacterial analysis. Nanoscale Res. Lett. 13 , 1–13 (2018).

Ahmad, M. et al. Phytogenic fabrication of ZnO and gold decorated ZnO nanoparticles for photocatalytic degradation of rhodamine B. J. Environ. Chem. Eng. 9 , 104725 (2021).

Kumar, S., Sharma, S. K., Kaushik, R. D. & Purohit, L. P. Chalcogen-doped zinc oxide nanoparticles for photocatalytic degradation of Rhodamine B under the irradiation of ultraviolet light. Mater. Today Chem. 20 , 100464 (2021).

Worathitanon, C. et al. High performance visible-light responsive Chl-Cu/ZnO catalysts for photodegradation of rhodamine B. Appl. Catal. B Environ. 241 , 359–366 (2019).

Palanisamy, B., Babu, C. M., Sundaravel, B., Anandan, S. & Murugesan, V. Sol–gel synthesis of mesoporous mixed Fe 2 O 3 /TiO 2 photocatalyst: Application for degradation of 4-chlorophenol. J. Hazard.Mater. https://doi.org/10.1016/j.jhazmat.2013.02.060 (2013).

Article   PubMed   Google Scholar  

Chen, X., Wu, Z., Liu, D. & Gao, Z. Preparation of ZnO photocatalyst for the efficient and rapid photocatalytic degradation of azo dyes. Nanoscale Res. Lett. https://doi.org/10.1186/s11671-017-1904-4 (2017).

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Chemistry Department , Faculty of Science, Port Said University, POB 42522, Port Said, Egypt

Nasser Mohammed Hosny & Islam Gomaa

Nanotechnology Research Centre (NTRC), The British University in Egypt (BUE), Suez Desert Road, El Sherouk City, Cairo, 11837, Egypt

Islam Gomaa

Chemical Engineering Department, The British University in Egypt (BUE), El Shrouk City, Cairo, Egypt

Maryam G. Elmahgary

Department of Chemical Engineering, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA, 02139, USA

Spectroscopy Department, National Research Centre, 33 El-Bohouth St., Dokki, Giza, 12622, Egypt

Medhat A. Ibrahim

Molecular Modeling and Spectroscopy Laboratory, Centre for Excellence for Advanced Science, National Research Centre, 33 El-Bohouth St, Dokki, Giza, 12622, Egypt

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N.M.H. Supervision, editing, and data interpretation, writing the manuscript; I.G., Conceptualization, investigation, methodology, experimental, preparation, writing and editing. M.G.E, Photo catalytic application, writing and results interpretations. M.A.I. Supervision, editing, and data interpretation. All authors have read and agreed to the published version of the manuscript.

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Correspondence to Nasser Mohammed Hosny or Medhat A. Ibrahim .

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Hosny, N.M., Gomaa, I., Elmahgary, M.G. et al. ZnO doped C: Facile synthesis, characterization and photocatalytic degradation of dyes. Sci Rep 13 , 14173 (2023). https://doi.org/10.1038/s41598-023-41106-4

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Received : 25 March 2023

Accepted : 22 August 2023

Published : 30 August 2023

DOI : https://doi.org/10.1038/s41598-023-41106-4

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The Potential of Nanoparticle-Mediated Macrophage Polarization for Solid Tumor Therapy: Evidence Synthesis and Temporal Monitoring

Cancer persists as a significant public health challenge despite treatment advances.  Colorectal cancer is especially a concern because its incidence and mortality are increasing in  young individuals. Solid tumors, such as colorectal cancer, are challenging to treat with  immunotherapies due to their immunosuppressive microenvironment preventing T cell infiltration.  Tumor-associated macrophages (TAMs) play a pivotal role in supporting this immunosuppression  by adopting an anti-inflammatory and pro-tumoral phenotype within the tumor microenvironment.  Leveraging nanoparticles to repolarize TAMs towards a proinflammatory and tumoricidal  phenotype holds promise for solid tumor therapy. However, clinical translation of cancer nanomedicines has been slow. This dissertation aims to address this through quantitative review  of the intersection between the colorectal cancer nanomedicine and macrophage polarization,  and by proposing a novel method of temporally tracking macrophage polarization using  bioluminescent reporter cells.  

Using eLDA topic modeling, the dissertation identifies six major topics in the intersection  of cancer medicine and macrophage polarization, providing insights into nanoparticle design  choices and therapeutic strategies across various cancer types. A scoping review and meta analysis of colorectal cancer nanomedicine over two decades reveal evolving nanoparticle design  strategies and their impact on macrophage polarization. We also demonstrate how a  nanoparticle’s ability to increase macrophages’ ratio of M1 to M2 polarization is correlated with  their efficacy at reducing tumor growth and increasing survival. This dissertation also includes a  technology assessment of how evidence synthesis of preclinical studies informs open science  policy.   

To better temporally track macrophage polarization, the dissertation introduces a method  utilizing THP-1 reporter cells with bioluminescently labeled polarization-relevant transcription  factors. We demonstrated how these reporter cells enable time-resolved activation curves for  tumor-associated macrophages, revealing unique NFκB activation profiles dependent on cancer  type that we linked to the tumor microenvironments immunogenicity. Furthermore, monitoring  monocyte to macrophage differentiation with this method highlights the importance of selecting appropriate differentiation protocols for the intended use. These examples demonstrate the  potential use of this bioluminescent platform to monitor macrophage polarization in response to  immunomodulatory treatments, like macrophage-targeted cancer nanomedicine.  

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• Dissertation
• Biomedical Engineering

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• Doctor of Philosophy (PhD)

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• Biomedical Engineering not elsewhere classified

2024 Outstanding Student Achievement Award: PhD Research Category

Anna smith ’24.

Anna Smith is a PhD candidate in the Graduate Program in Molecular and Translational Medicine (MTM). She has been at Boston University for almost five years, having matriculated into the PhD Program in Biomedical Sciences in Fall 2019.

Anna is completing her dissertation research in the lab of Associate Professor of Medicine Valerie Gouon-Evans, PhD, PharmD. Dr. Gouon-Evans directs the Boston University Liver Biologists (BULB) Program and is the associate director of the MTM program. Anna’s research focuses on finding alternatives to liver transplantation that transplant healthy liver cells instead of an entire organ. She defended her dissertation, “Human Primary and iPSC-Derived Hepatocyte Cell Therapies to Treat Liver Disease,” in March 2024 and will graduate in May 2024.  

Anna’s dissertation research won her this year’s Outstanding Student Achievement Award in the PhD Research Category. Read more about her work below!

Can you please describe the research project that led to your recognition with this award?

Currently, the main treatment for end stage liver disease is a liver transplantation; however, there is a donor organ shortage. My research project is focused on finding alternatives to liver transplantation. What we propose is to treat liver diseases by transplanting healthy liver cells instead of an entire organ.

I have been exploring liver cell transplantation in mouse models that mimic actual human liver diseases. We discovered in the lab that liver cell transplantation alone is not sufficient to treat liver disease. Next, we started administering supportive factors to help transplanted cells. Excitingly, we found that this significantly improved liver cell engraftment and actually helped treat liver disease in mice. To deliver these supportive factors to transplanted cells, we took advantage of the nucleoside modified mRNA in lipid nanoparticles (mRNA-LNP) platform.

The mRNA-LNP platform is the same technology that is used for COVID-19 vaccines, which means that we are developing a therapeutic that has strong potential to be used in humans too. We are also currently publishing this work so that it is available to the greater scientific community.

What sparked your interest with conducting research, and how did you choose this area of focus for your project?

My undergraduate mentor in college sparked my interest in research. She was a strong female role model who I really looked up to, and she helped me find the right career path based on my interests in science, helping others and mentorship. I chose to focus on a liver regeneration project because I was inspired by the Alpha-1 Foundation community. The Alpha-1 Foundation is a community of researchers, doctors, patients and their families who are all working to find a cure for Alpha-1 liver disease. This inspired me to investigate how we could use our tools in the lab to cure liver diseases such as Alpha-1.

How do you believe your research is significant to your field and/or addresses a particular issue or gap in knowledge?

My research has the potential to overcome critical barriers to the clinical translation of liver cell therapies. Currently, liver cell therapies are not widely used to treat human patients. With discoveries that I made in the lab, along with the help of all of my colleagues, liver cell therapies are a more viable alternative to organ transplantation than ever before.

Can you discuss any challenges you’ve faced during the research project and how you overcame them?

Doing scientific research always comes with significant challenges, both in and out of the lab. The most significant hurdle that we had to overcome was trying to figure out the key to get liver cells to engraft in mice. Once we figured out that the liver cells needed important supportive growth factors, we had to tackle the technical hurdle of how to deliver these factors in a living animal. We overcame these challenges and obstacles by being resilient and asking for help. We ultimately achieved success because of our strong collaborations with top scientists at other universities and companies across the world.

Looking ahead, do you have any plans to further explore the topic of your research?

Yes! I am looking forward to further exploring liver related therapeutics by working at a biotech company after graduation.

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