Evaluation of the Photocatalytic and Antimicrobial Properties of Cu-Doped ZnO Nanoparticles Synthesized by Phytochemical Methods

Abstract:

In this study, zinc oxide (ZnO) and copper-doped zinc oxide nanoparticles (Cu-ZnO NPs) were synthesized using a green method that employed Rosmarinus officinalis leaf extract as a reducing agent. Copper was incorporated as a dopant at concentrations of 3% and 5%. Zinc acetate dihydrate and copper acetate served as the precursors and dopants, respectively. The synthesized samples were characterized utilizing a range of techniques, including XRD, SEM, EDX, Raman spectroscopy, UV-visible spectroscopy, and PL spectroscopy. XRD and Raman spectroscopy analyses validated the effective incorporation of Cu²⁺ ions into the ZnO wurtzite structure. SEM analysis indicated that the nanoparticles displayed a spherical morphology, while EDX analysis confirmed the presence of zinc (Zn), copper (Cu), and oxygen (O), thereby validating the sample's purity. UV-visible spectra revealed a reduction in the optical band gap with increasing Cu concentration. Photoluminescence peaks observed at 383 nm and 565 nm were ascribed to electron transitions from deep donor levels, particularly from Zn interstitials to Zn and oxygen vacancies. The 5% Cu-doped ZnO NPs demonstrated the highest photocatalytic activity, achieving 90% degradation of Rhodamine B (RhB) dye under UV irradiation in 135 minutes. They also exhibited significant antibacterial activity, particularly against Gram-positive bacteria (Staphylococcus aureus) compared to Gram-negative bacteria (Escherichia coli).

• Periodical: Journal of Nano Research (Volume 87)
• Pages: 75-94
• DOI: https://doi.org/10.4028/p-2IPJQj
• Online since: March 2025
• Authors: Khaled Chettah*, Smail Boudjadar, Badreddine Toubal, Hassan Guendouz
• Keywords: Antimicrobial Activity, Cu-Doped ZnO, Green Synthesis, Nanoparticle, Photocatalytic Activity, Rhodamine b

References

[1] L. Lin, H. Yang, X. Xu, Effects of Water Pollution on Human Health and Disease Heterogeneity: A Review, Frontiers in environmental science. 10 (2022) 880246.

[2] R. Qadri, M.A. Faiq, Freshwater Pollution: Effects on Aquatic Life and Human Health, Fresh water pollution dynamics and remediation. (2020) 15-26.

DOI: 10.1007/978-981-13-8277-2_2

[3] M. Shabir, M. Yasin, M. Hussain, I. Shafiq, P. Akhter, A.-S. Nizami, B.-H. Jeon, Y.-K. Park, A Review on Recent Advances in the Treatment of Dye-Polluted Wastewater, Journal of Industrial and Engineering Chemistry. 112 (2022) 1-19.

DOI: 10.1016/j.jiec.2022.05.013

[4] V. Katheresan, J. Kansedo, S.Y. Lau, Efficiency of Various Recent Wastewater Dye Removal Methods: A Review, Journal of environmental chemical engineering. 6 (2018) 4676-4697.

DOI: 10.1016/j.jece.2018.06.060

[5] R. Rashid, I. Shafiq, P. Akhter, M.J. Iqbal, M. Hussain, A State-of-the-Art Review on Wastewater Treatment Techniques: The Effectiveness of Adsorption Method, Environmental Science and Pollution Research. 28 (2021) 9050-9066.

DOI: 10.1007/s11356-021-12395-x

[6] D. Ayodhya, G. Veerabhadram, A Review on Recent Advances in Photodegradation of Dyes Using Doped and Heterojunction Based Semiconductor Metal Sulfide Nanostructures for Environmental Protection, Materials today energy. 9 (2018) 83-113.

DOI: 10.1016/j.mtener.2018.05.007

[7] T.Y. Ahmed, S.B. Aziz, E.M. Dannoun, New Photocatalytic Materials Based on Alumina with Reduced Band Gap: A Dft Approach to Study the Band Structure and Optical Properties, Heliyon. 10 (2024).

DOI: 10.1016/j.heliyon.2024.e27029

[8] S.A. Mousa, D. Wissa, H. Hassan, A. Ebnalwaled, S. Khairy, Enhanced Photocatalytic Activity of Green Synthesized Zinc Oxide Nanoparticles Using Low-Cost Plant Extracts, Scientific Reports. 14 (2024) 16713.

DOI: 10.1038/s41598-024-66975-1

[9] S. Kumar, A. Kumar, T. Malhotra, S. Verma, Characterization of Structural, Optical and Photocatalytic Properties of Silver Modified Hematite (Α-Fe2o3) Nanocatalyst, Journal of Alloys and Compounds. 904 (2022) 164006.

DOI: 10.1016/j.jallcom.2022.164006

[10] J. Wang, Z. Wang, W. Wang, Y. Wang, X. Hu, J. Liu, X. Gong, W. Miao, L. Ding, X. Li, Synthesis, Modification and Application of Titanium Dioxide Nanoparticles: A Review, Nanoscale. 14 (2022) 6709-6734.

DOI: 10.1039/d1nr08349j

[11] J. Mathai, Investigation of Non Linear and Photocatalytic Properties of Pristine and Cr Doped Zno Nanorods. (2022).

[12] Y. Sun, W. Zhang, Q. Li, H. Liu, X. Wang, Preparations and Applications of Zinc Oxide Based Photocatalytic Materials, Advanced Sensor and Energy Materials. (2023) 100069.

DOI: 10.1016/j.asems.2023.100069

[13] I. Kim, K. Viswanathan, G. Kasi, S. Thanakkasaranee, K. Sadeghi, J. Seo, Zno Nanostructures in Active Antibacterial Food Packaging: Preparation Methods, Antimicrobial Mechanisms, Safety Issues, Future Prospects, and Challenges, Food Reviews International. 38 (2022) 537-565.

DOI: 10.1080/87559129.2020.1737709

[14] F. Qiao, K. Sun, H. Chu, J. Wang, Y. Xie, L. Chen, T. Yan, Design Strategies of Zno Heterojunction Arrays Towards Effective Photovoltaic Applications, Battery Energy. 1 (2022) 20210008.

DOI: 10.1002/bte2.20210008

[15] A. Piras, C. Olla, G. Reekmans, A.-S. Kelchtermans, D. De Sloovere, K. Elen, C.M. Carbonaro, L. Fusaro, P. Adriaensens, A. Hardy, 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, International Journal of Molecular Sciences. 23 (2022) 15459.

DOI: 10.3390/ijms232415459

[16] C.B. Ong, L.Y. Ng, A.W. Mohammad, A Review of Zno Nanoparticles as Solar Photocatalysts: Synthesis, Mechanisms and Applications, Renewable and Sustainable Energy Reviews. 81 (2018) 536-551.

DOI: 10.1016/j.rser.2017.08.020

[17] A.W. Cohn, N. Janssen, J.M. Mayer, D.R. Gamelin, Photocharging Zno Nanocrystals: Picosecond Hole Capture, Electron Accumulation, and Auger Recombination, The Journal of Physical Chemistry C. 116 (2012) 20633-20642.

DOI: 10.1021/jp3075942

[18] M. Xu, Y. Chen, W. Hu, Y. Liu, Q. Zhang, H. Yuan, X. Wang, J. Zhang, K. Luo, J. Li, Designed Synthesis of Microstructure and Defect-Controlled Cu-Doped Zno–Ag Nanoparticles: Exploring High-Efficiency Sunlight-Driven Photocatalysts, Journal of Physics D: Applied Physics. 53 (2019) 025106.

DOI: 10.1088/1361-6463/ab4bfd

[19] S.A. Ayon, S. Hasan, M.M. Billah, S.S. Nishat, A. Kabir, Improved Luminescence and Photocatalytic Properties of Sm3+-Doped Zno Nanoparticles Via Modified Sol–Gel Route: A Unified Experimental and Dft+ U Approach, Journal of Rare Earths. 41 (2023) 550-560.

DOI: 10.1016/j.jre.2022.03.004

[20] A. Singh, F. Wan, K. Yadav, A. Salvi, P. Thakur, A. Thakur, Synergistic Effect of Zno Nanoparticles with Cu2+ Doping on Antibacterial and Photocatalytic Activity, Inorganic Chemistry Communications. 157 (2023) 111425.

DOI: 10.1016/j.inoche.2023.111425

[21] E.I. Naik, H.B. Naik, B.K. Swamy, R. Viswanath, I.S. Gowda, M. Prabhakara, K. Chetankumar, Influence of Cu Doping on Zno Nanoparticles for Improved Structural, Optical, Electrochemical Properties and Their Applications in Efficient Detection of Latent Fingerprints, Chemical Data Collections. 33 (2021) 100671.

DOI: 10.1016/j.cdc.2021.100671

[22] R. Ghorbali, G. Essalah, A. Ghoudi, H. Guermazi, S. Guermazi, A. El Hdiy, H. Benhayoune, B. Duponchel, A. Oueslati, G. Leroy, The Effect of (in, Cu) Doping and Co-Doping on Physical Properties and Organic Pollutant Photodegradation Efficiency of Zno Nanoparticles for Wastewater Remediation, Ceramics International. 49 (2023) 33828-33841.

DOI: 10.1016/j.ceramint.2023.08.076

[23] R. Beura, S. Rajendran, M.G. Pinilla, P. Thangadurai, Enhanced Photo-Induced Catalytic Activity of Cu Ion Doped Zno-Graphene Ternary Nanocomposite for Degrading Organic Dyes, Journal of Water Process Engineering. 32 (2019) 100966.

DOI: 10.1016/j.jwpe.2019.100966

[24] M.S. Hossain, M.Y.A. Mollah, M.A.B.H. Susan, M.M. Islam, Role of in Situ Electrogenerated Reactive Oxygen Species Towards Degradation of Organic Dye in Aqueous Solution, Electrochimica Acta. 344 (2020) 136146.

DOI: 10.1016/j.electacta.2020.136146

[25] L. Xiong, J. Tang, Strategies and Challenges on Selectivity of Photocatalytic Oxidation of Organic Substances, Advanced Energy Materials. 11 (2021) 2003216.

DOI: 10.1002/aenm.202003216

[26] A.F. El-Sayed, W.M. Aboulthana, M.A. Sherief, G.T. El-Bassyouni, S.M. Mousa, Synthesis, Structural, Molecular Docking, and in Vitro Biological Activities of Cu-Doped Zno Nanomaterials, Scientific Reports. 14 (2024) 9027.

DOI: 10.1038/s41598-024-59088-2

[27] A. Tsogoo, N. Tsedev, A. Gibaud, P. Daniel, A. Kassiba, M. Fukuda, Y. Kusano, M. Azuma, N. Tsogbadrakh, G. Ragchaa, Experimental and Ab Initio Studies on the Structural, Magnetic, Photocatalytic, and Antibacterial Properties of Cu-Doped Zno Nanoparticles, RSC advances. 13 (2023) 1256-1266.

DOI: 10.1039/d2ra07204a

[28] J. Ramos-Zúñiga, N. Bruna, J.M. Pérez-Donoso, Toxicity Mechanisms of Copper Nanoparticles and Copper Surfaces on Bacterial Cells and Viruses, International Journal of Molecular Sciences. 24 (2023) 10503.

DOI: 10.3390/ijms241310503

[29] B. Bharti, H. Li, Z. Ren, R. Zhu, Z. Zhu, Recent Advances in Sterilization and Disinfection Technology: A Review, Chemosphere. 308 (2022) 136404.

DOI: 10.1016/j.chemosphere.2022.136404

[30] A. Zaater, M.O. Serhoud, I. Ben Amor, S. Zeghoud, A. Hemmami, A. Rebiai, Y. Bouras, A.T. Laiche, A. Alsalme, D. Cornu, Exploring the Potential of a Ephedra Alata Leaf Extract: Phytochemical Analysis, Antioxidant Activity, Antibacterial Properties, and Green Synthesis of Zno Nanoparticles for Photocatalytic Degradation of Methylene Blue, Frontiers in Chemistry. 12 (2024) 1367552.

DOI: 10.3389/fchem.2024.1367552

[31] P. Basnet, T.I. Chanu, D. Samanta, S. Chatterjee, A Review on Bio-Synthesized Zinc Oxide Nanoparticles Using Plant Extracts as Reductants and Stabilizing Agents, Journal of Photochemistry and Photobiology B: Biology. 183 (2018) 201-221.

DOI: 10.1016/j.jphotobiol.2018.04.036

[32] S. Waseem, Z.U. Nisa, T. Zeeshan, M.D. Ali, T. Begum, Z.N. Kayani, I. Ali, A. Ayub, Green Synthesis of Zno Nanoparticles Using Nigella Sativa Seed Extract for Antibacterial Activities, Nano-Structures & Nano-Objects. 38 (2024) 101212.

DOI: 10.1016/j.nanoso.2024.101212

[33] S. Sasi, P.F. Fasna, T.B. Sharmila, C.J. Chandra, J.V. Antony, V. Raman, A.B. Nair, H.N. Ramanathan, Green Synthesis of Zno Nanoparticles with Enhanced Photocatalytic and Antibacterial Activity, Journal of Alloys and Compounds. 924 (2022) 166431.

DOI: 10.1016/j.jallcom.2022.166431

[34] H. Sadiq, F. Sher, S. Sehar, E.C. Lima, S. Zhang, H.M. Iqbal, F. Zafar, M. Nuhanović, Green Synthesis of Zno Nanoparticles from Syzygium Cumini Leaves Extract with Robust Photocatalysis Applications, Journal of Molecular Liquids. 335 (2021) 116567.

DOI: 10.1016/j.molliq.2021.116567

[35] F.V. Molefe, L.F. Koao, B.F. Dejene, H.C. Swart, Phase Formation of Hexagonal Wurtzite Zno through Decomposition of Zn (Oh) 2 at Various Growth Temperatures Using Cbd Method, Optical materials. 46 (2015) 292-298.

DOI: 10.1016/j.optmat.2015.04.034

[36] K.V. Chandekar, M. Shkir, B.M. Al-Shehri, S. AlFaify, R.G. Halor, A. Khan, K.S. Al-Namshah, M.S. Hamdy, Visible Light Sensitive Cu Doped Zno: Facile Synthesis, Characterization and High Photocatalytic Response, Materials Characterization. 165 (2020) 110387.

DOI: 10.1016/j.matchar.2020.110387

[37] M. Ahmad, E. Ahmed, Z. Hong, X. Jiao, T. Abbas, N. Khalid, Enhancement in Visible Light-Responsive Photocatalytic Activity by Embedding Cu-Doped Zno Nanoparticles on Multi-Walled Carbon Nanotubes, Applied Surface Science. 285 (2013) 702-712.

DOI: 10.1016/j.apsusc.2013.08.114

[38] P.G. Devi, A.S. Velu, Synthesis, Structural and Optical Properties of Pure Zno and Co- Doped Zno Nanoparticles Prepared by the Co-Precipitation Method, Journal of Theoretical and Applied Physics. 10 (2016) 233-240.

DOI: 10.1007/s40094-016-0221-0

[39] Y. Zhou, Y. Rao, L. Zhang, S. Ju, H. Wang, Machine-Learning Prediction of Vegard's Law Factor and Volume Size Factor for Binary Substitutional Metallic Solid Solutions, Acta Materialia. 237 (2022) 118166.

DOI: 10.1016/j.actamat.2022.118166

[40] S. Singhal, J. Kaur, T. Namgyal, R. Sharma, Cu-Doped Zno Nanoparticles: Synthesis, Structural and Electrical Properties, Physica B: Condensed Matter. 407 (2012) 1223-1226.

DOI: 10.1016/j.physb.2012.01.103

[41] Y. Qi, A. Kosinova, A.R. Kilmametov, B.B. Straumal, E. Rabkin, Plastic Flow and Microstructural Instabilities During High-Pressure Torsion of Cu/Zno Composites, Materials Characterization. 145 (2018) 389-401.

DOI: 10.1016/j.matchar.2018.09.001

[42] M.S. Sharrouf, Preparation and Characterization of Magnetic Diluted Semiconductors Samples. (2015).

[43] L. Umaralikhan, M.J.M. Jaffar, Green Synthesis of Zno and Mg Doped Zno Nanoparticles, and Its Optical Properties, Journal of Materials Science: Materials in Electronics. 28 (2017) 7677-7685.

DOI: 10.1007/s10854-017-6461-1

[44] D.A. Wilson, K. Gurung, M.A. Langell, Effect of Zinc Substitution on the Growth Morphology of Zno-Cuo Tenorite Solid Solutions, Journal of Crystal Growth. 562 (2021) 126062.

DOI: 10.1016/j.jcrysgro.2021.126062

[45] R. Priya, P. Sahay, N. Saxena, P. Rajput, V. Chawla, R. Sharma, O. Sinha, R. Krishna, Systematic Study of Ni, Cu Co-Doped Zno Nanoparticles for Uv Photodetector Application, Journal of Materials Science: Materials in Electronics. 32 (2021) 2011-2025.

DOI: 10.1007/s10854-020-04968-2

[46] A.M. Abd-Elnaiem, M. Rashad, T. Hanafy, N. Shaalan, Improvement of Optical Properties of Functionalized Polyvinyl Alcohol-Zinc Oxide Hybrid Nanocomposites for Wide Uv Optoelectronic Applications, Journal of Inorganic and Organometallic Polymers and Materials. 33 (2023) 2429-2444.

DOI: 10.1007/s10904-023-02616-w

[47] A. Bourebia, A. Bouaine, H. Guendouz, Appearance of Amorphous Phase in Crystalline in-Y Codoped Zno Thin Films, Bulletin of Materials Science. 47 (2024) 89.

DOI: 10.1007/s12034-024-03146-y

[48] A. Trovarelli, J. Llorca, Ceria Catalysts at Nanoscale: How Do Crystal Shapes Shape Catalysis?, ACS catalysis. 7 (2017) 4716-4735.

DOI: 10.1021/acscatal.7b01246

[49] P. Labhane, V. Huse, L. Patle, A. Chaudhari, G. Sonawane, Synthesis of Cu Doped Zno Nanoparticles: Crystallographic, Optical, Ftir, Morphological and Photocatalytic Study, Journal of Materials Science and Chemical Engineering. 3 (2015) 39-51.

DOI: 10.4236/msce.2015.37005

[50] M. Barhoush, A.K.M. Alsmadi, B. Salameh, M. Shatnawi, G. Alna'washi, Role of Defects in Tailoring Optical, Electronic, and Luminescent Properties of Cu-Doped Zno Films, Ceramics International. 49 (2023) 32538-32548.

DOI: 10.1016/j.ceramint.2023.07.218

[51] S. Sivakumar, Y. Robinson, N.A. Mala, Studies on Photocatalytic Performance and Supercapacitor Applications of Undoped and Cu-Doped Zno Nanoparticles, Applied Surface Science Advances. 12 (2022) 100344.

DOI: 10.1016/j.apsadv.2022.100344

[52] C. Kranert, Investigation of Wide-Bandgap Semiconductors by Uv Raman Spectroscopy: Resonance Effects and Material Characterization. (2015).

[53] V.M. Lage, C. Rodríguez-Fernández, F.S. Vieira, R.T. da Silva, M.I.B. Bernardi, M.M. de Lima Jr, A. Cantarero, H.B. de Carvalho, On the Vibrational Properties of Transition Metal Doped Zno: Surface, Defect, and Bandgap Engineering, Acta Materialia. 259 (2023) 119258.

DOI: 10.1016/j.actamat.2023.119258

[54] V. Gurylev, T.P. Perng, Defect Engineering of Zno: Review on Oxygen and Zinc Vacancies, Journal of the European Ceramic Society. 41 (2021) 4977-4996.

DOI: 10.1016/j.jeurceramsoc.2021.03.031

[55] M.K. Gora, A. Kumar, S. Kumar, J. Nehra, B.L. Choudhary, S.N. Dolia, R.K. Singhal, The Study of Optical, Structural and Magnetic Properties of Cu-Doped Zno Nanoparticles, Journal of Materials Science: Materials in Electronics. 34 (2023) 288.

DOI: 10.1007/s10854-022-09713-5

[56] J. Marselie, V. Fauzia, I. Sugihartono, The Effect of Cu Dopant on Morphological, Structural and Optical Properties of Zno Nanorods Grown on Indium Tin Oxide Substrate, Journal of Physics: Conference Series, IOP Publishing, 2017, p.012014.

DOI: 10.1088/1742-6596/817/1/012014

[57] M. Dhonde, K. Sahu, V. Murty, S.S. Nemala, P. Bhargava, Surface Plasmon Resonance Effect of Cu Nanoparticles in a Dye Sensitized Solar Cell, Electrochimica Acta. 249 (2017) 89-95.

DOI: 10.1016/j.electacta.2017.07.187

[58] P.R. Jubu, O. Obaseki, A. Nathan-Abutu, F. Yam, Y. Yusof, M. Ochang, Dispensability of the Conventional Tauc's Plot for Accurate Bandgap Determination from Uv–Vis Optical Diffuse Reflectance Data, Results in Optics. 9 (2022) 100273.

DOI: 10.1016/j.rio.2022.100273

[59] H. Guendouz, A. Bouaine, N. Brihi, Ultrawide Bandgap High near Ultraviolet Transparency Amorphous Sn–Al Co-Doped Zno Thin Films, Journal of Non-Crystalline Solids. 569 (2021) 121001.

DOI: 10.1016/j.jnoncrysol.2021.121001

[60] A. Khalid, P. Ahmad, A. Khan, Effect of Cu Doping on Zno Nanoparticles as a Photocatalyst for the Removal of Organic Wastewater (Retraction of Vol 2022, Art No 9459886, 2022), HINDAWI LTD ADAM HOUSE, 3RD FLR, 1 FITZROY SQ, LONDON, W1T 5HF, ENGLAND, 2023.

[61] J. Wang, R. Chen, L. Xiang, S. Komarneni, Synthesis, Properties and Applications of Zno Nanomaterials with Oxygen Vacancies: A Review, Ceramics International. 44 (2018) 7357-7377.

DOI: 10.1016/j.ceramint.2018.02.013

[62] N. Kochnev, D. Tkachenko, D. Kirsanov, N. Bobrysheva, M. Osmolowsky, M. Voznesenskiy, O. Osmolovskaya, Regulation and Prediction of Defect-Related Properties in Zno Nanosheets: Synthesis, Morphological and Structural Parameters, Dft Study and Qspr Modelling, Applied Surface Science. 621 (2023) 156828.

DOI: 10.1016/j.apsusc.2023.156828

[63] V. Shanmugam, K.S. Jeyaperumal, Investigations of Visible Light Driven Sn and Cu Doped Zno Hybrid Nanoparticles for Photocatalytic Performance and Antibacterial Activity, Applied Surface Science. 449 (2018) 617-630.

DOI: 10.1016/j.apsusc.2017.11.167

[64] Y. Xu, H. Li, B. Sun, P. Qiao, L. Ren, G. Tian, B. Jiang, K. Pan, W. Zhou, Surface Oxygen Vacancy Defect-Promoted Electron-Hole Separation for Porous Defective Zno Hexagonal Plates and Enhanced Solar-Driven Photocatalytic Performance, Chemical Engineering Journal. 379 (2020) 122295.

DOI: 10.1016/j.cej.2019.122295

[65] A. Khalid, P. Ahmad, A.I. Alharthi, S. Muhammad, M.U. Khandaker, M.R.I. Faruque, I.U. Din, M.A. Alotaibi, A. Khan, Synergistic Effects of Cu-Doped Zno Nanoantibiotic against Gram-Positive Bacterial Strains, Plos one. 16 (2021) e0251082.

DOI: 10.1371/journal.pone.0251082

[66] T.D. Tavares, J.C. Antunes, J. Padrão, A.I. Ribeiro, A. Zille, M.T.P. Amorim, F. Ferreira, H.P. Felgueiras, Activity of Specialized Biomolecules against Gram-Positive and Gram-Negative Bacteria, Antibiotics. 9 (2020) 314.

DOI: 10.3390/antibiotics9060314

[67] W. Wei, J. Li, Z. Liu, Y. Deng, D. Chen, P. Gu, G. Wang, X. Fan, Distinct Antibacterial Activity of a Vertically Aligned Graphene Coating against Gram-Positive and Gram-Negative Bacteria, Journal of Materials Chemistry B. 8 (2020) 6069-6079.

DOI: 10.1039/d0tb00417k

[68] C.A. Juan, J.M. Pérez de la Lastra, F.J. Plou, E. Pérez-Lebeña, The Chemistry of Reactive Oxygen Species (Ros) Revisited: Outlining Their Role in Biological Macromolecules (DNA, Lipids and Proteins) and Induced Pathologies, International journal of molecular sciences. 22 (2021) 4642.

DOI: 10.3390/ijms22094642

[69] X. Bai, Y. Cao, B. Zhu, R. Liu, J. Dong, H. Yang, Enhancement of Photocatalytic Antimicrobial Performance Via Generation and Diffusion of Ros, Science for Energy and Environment. (2024) 7-7.

DOI: 10.53941/see.2024.100007

[70] M. Benamara, K.I. Nassar, M. Essid, S. Frick, R. Rugmini, K. Sekhar, J.P. Silva, Visible Light-Driven Removal of Rhodamine B Using Indium-Doped Zinc Oxide Prepared by Sol–Gel Method, Journal of Sol-Gel Science and Technology. 111 (2024) 553-565.

DOI: 10.1007/s10971-024-06471-0

[71] T. Varadavenkatesan, E. Lyubchik, S. Pai, A. Pugazhendhi, R. Vinayagam, R. Selvaraj, Photocatalytic Degradation of Rhodamine B by Zinc Oxide Nanoparticles Synthesized Using the Leaf Extract of Cyanometra Ramiflora, Journal of photochemistry and Photobiology B: Biology. 199 (2019) 111621.

DOI: 10.1016/j.jphotobiol.2019.111621

[72] M. Rafique, R. Tahir, N. Khalid, M.B. Tahir, M. Irshad, S. Gillani, A. Usman, K. Shahzad, A. Mahmood Ali, S. Muhammad, Hydrothermal Synthesis of an Efficient and Visible Light Responsive Pure and Strontium Doped Zinc Oxide Nano-Hexagonal Photocatalysts for Photodegradation of Rhodamine B Dye, Applied Nanoscience. 11 (2021) 1045-1056.

DOI: 10.1007/s13204-021-01669-y