Structural, Optical, and Photocatalytic Properties of Sol–Gel-Derived ZnO Nanoparticles for Methylene Blue Degradation
Abstract
Zinc oxide (ZnO) nanoparticles are attractive photocatalysts due to their wide band gap, chemical stability, and nanoscale-dependent properties. Herein, ZnO nanoparticles were synthesized and systematically characterized to correlate their structural and optical properties with photocatalytic performance. Raman spectroscopy and X-ray diffraction confirmed the formation of a single-phase wurtzite ZnO structure with high crystallinity. UV–Vis diffuse reflectance spectroscopy revealed a distinct absorption edge in the UV region, and the optical band gap was determined to be 3.07 eV using the Kubelka–Munk–Tauc method. The photocatalytic activity of the synthesized ZnO was evaluated via methylene blue degradation under UV irradiation. Time-resolved UV–Vis absorption measurements showed a gradual decrease in the characteristic absorption peak at 660–670 nm, indicating effective dye degradation. A photocatalytic degradation efficiency of 60.55% was achieved after 150 min of irradiation. Kinetic analysis demonstrated that the degradation process followed pseudo-first-order kinetics with an apparent rate constant of 0.0062 min⁻¹. These results demonstrate that the synthesized ZnO nanoparticles exhibit efficient UV-driven photocatalytic activity, highlighting their potential for nanoscale photocatalyst applications. The structure–property–performance correlation established in this work provides insight for further nanostructure and defect engineering strategies to enhance photocatalytic efficiency.
Keywords
Full Text:
PDFReferences
H. N. Abdelhamid, “Photocatalytic degradation of organic dyes using ZIF-67,” Surf. Interfaces, vol. 73, p.
107580, Sep. 2025, doi: 10.1016/j.surfin.2025.107580.
[2] A. S. Belousov et al., “Regulating of MnO2 photocatalytic activity in degradation of organic dyes by
polymorphic engineering,” Solid State Sci., vol. 132, p. 106997, Oct. 2022, doi:10.1016/j.solidstatesciences.2022.106997.
[3] J. N. Tsaviv, I. S. Eneji, R. Sha’Ato, I. Ahemen, P. R. Jubu, and Y. Yusof, “Photodegradation, kinetics and non-linear error functions of methylene blue dye using SrZrO3 perovskite photocatalyst,” Heliyon, vol. 10, no. 14, p. e34517, Jul. 2024, doi: 10.1016/j.heliyon.2024.e34517.
[4] S. Rasheed et al., “Photocatalytic Degradation of Methylene Blue by Engineering Tungstic Acid@ZIF‐67 Cocatalyst,” ChemistrySelect, vol. 9, no. 46, p. e202403807, Dec. 2024, doi: 10.1002/slct.202403807.
[5] D. P. Benu et al., “Macroemulsion-mediated synthesis of fibrous ZnO microrods and their surface morphology
contribution to the high photocatalytic degradation rate,” New J. Chem., vol. 47, no. 1, pp. 428–442, 2023,
doi: 10.1039/D2NJ04862K.
[6] A. Andriani et al., “Role of urea on the structural, textural, and optical properties of macroemulsion-assisted
synthesized holey ZnO nanosheets for photocatalytic applications,” New J. Chem., vol. 46, no. 20, pp. 9897–
9908, 2022, doi: 10.1039/D2NJ00184E.
[7] C. C. Christanti and D. P. Benu, “Low-Temperature Synthesis of ZnO Nanoparticles Using a Water-Methanol
Solvent for Rhodamine B Photodegradation,” J. Beta Kim., vol. 5, no. 1, pp. 62–69, Apr. 2025, doi:
10.35508/jbk.v5i1.21305.
[8] V. Nedelkovski, M. Radovanović, and M. Antonijević, “Advances in Photocatalytic Degradation of Crystal
Violet Using ZnO-Based Nanomaterials and Optimization Possibilities: A Review,” ChemEngineering, vol.
9, no. 6, p. 120, 2025, doi: 10.3390/chemengineering9060120.
[9] T. Rodríguez-Flores, I. Hernández-Pérez, G. E. de la Huerta-Hernández, Y. Ayala-Parada, J. G. Cadena-
Silva, and C. Haro-Pérez, “Comparison of Photocatalytic Performance of Sonochemically Synthesized ZnO
with Different Capping Agents,” ACS Omega, vol. 10, no. 28, pp. 30181–30193, Jul. 2025, doi:10.1021/acsomega.5c00929.
[10] C. C. Christanti and D. P. Benu, “Sintesis ZnO Berstruktur Nano Menggunakan Campuran Pelarut Air-Etilen
Glikol dan Karakterisasi Struktur, Morfologi, dan Energi Celah Pita Partikel,” J. Chem. Sci. App., vol. 2, no.
2, pp. 27–30, 2024.
[11] I. A. Ahmad and Y. H. Mohammed, “Synthesis of ZnO nanowires by thermal chemical vapor deposition
technique: Role of oxygen flow rate,” Micro Nanostructures, vol. 181, p. 207628, Sep. 2023, doi:10.1016/j.micrna.2023.207628.
[12] Y.-H. Huang, Y.-T. Chuang, H.-W. Lin, and C.-N. Liao, “Single-Step Electrodeposition of ZnO Nanoparticles
Decorated (111)-Textured Cu2O Films with Enhanced Photoelectrochemical Properties,” Inorg. Chem., vol. 64, no. 33, pp. 16950–16959, Aug. 2025, doi: 10.1021/acs.inorgchem.5c02573.
[13] J. N. Hasnidawani, H. N. Azlina, H. Norita, N. N. Bonnia, S. Ratim, and E. S. Ali, “Synthesis of ZnO Nanostructures Using Sol-Gel Method,” 5th Int. Conf. Recent Adv. Mater. Miner. Environ. RAMM 2nd Int. Postgrad. Conf. Mater. Miner. Polym. MAMIP, vol. 19, pp. 211–216, Jan. 2016, doi:
10.1016/j.proche.2016.03.095.
[14] S. Kanwal, M. Tahir Khan, V. Tirth, A. Algahtani, T. Al-Mughanam, and A. Zaman, “Room-Temperature Ferromagnetism in Mn-Doped ZnO Nanoparticles Synthesized by the Sol–Gel Method,” ACS Omega, vol. 8, no. 31, pp. 28749–28757, Aug. 2023, doi: 10.1021/acsomega.3c03418.
[15] J. C. Anaya-Zavaleta et al., “ZnO Nanoparticles by Hydrothermal Method: Synthesis and Characterization,”
Technologies, vol. 13, no. 1, p. 18, 2025, doi: 10.3390/technologies13010018.
[16] J. Pei et al., “Advancements in the Synthesis and Functionalization of Zinc Oxide-Based Nanomaterials for
Enhanced Oral Cancer Therapy,” Molecules, vol. 29, no. 11, p. 2706, 2024, doi:10.3390/molecules29112706.
[17] Y. Wang, X. Zhang, A. Wang, X. Li, G. Wang, and L. Zhao, “Synthesis of ZnO nanoparticles from microemulsions in a flow type microreactor,” Chem. Eng. J., vol. 235, pp. 191–197, Jan. 2014, doi: 10.1016/j.cej.2013.09.020.
[18] M. Kumar and C. Sasikumar, “Electrodeposition of Nanostructured ZnO Thin Film: A Review,” Am. J. Mater.
Sci. Eng., vol. 2, no. 2, pp. 18–23, May 2014, doi: 10.12691/ajmse-2-2-2.
[19] J. Lee, A. J. Easteal, U. Pal, and D. Bhattacharyya, “Evolution of ZnO nanostructures in sol–gel synthesis,”
Curr. Appl. Phys., vol. 9, no. 4, pp. 792–796, Jul. 2009, doi: 10.1016/j.cap.2008.07.018.
[20] R. Cuscó et al., “Temperature dependence of Raman scattering in ZnO,” Phys. Rev. B, vol. 75, no. 16, p.165202, Apr. 2007, doi: 10.1103/PhysRevB.75.165202.
[21] M. Manica et al., “Morphological and Optical Properties of RE-Doped ZnO Thin Films Fabricated Using Nanostructured Microclusters Grown by Electrospinning–Calcination,” Nanomaterials, vol. 15, no. 17, p.
1369, 2025, doi: 10.3390/nano15171369.
[22] M. Šćepanović, M. Grujić-Brojčin, K. Vojisavljević, S. Bernik, and T. Srećković, “Raman study of structural disorder in ZnO nanopowders,” J. Raman Spectrosc., vol. 41, no. 9, pp. 914–921, Sep. 2010, doi:
10.1002/jrs.2546.[23] S. Marković et al., “Effect of PEO molecular weight on sunlight induced photocatalytic activity of ZnO/PEO
composites,” Sol. Energy, vol. 127, pp. 124–135, Apr. 2016, doi: 10.1016/j.solener.2016.01.026.
[24] M. Schreyer, L. Guo, S. Thirunahari, F. Gao, and M. Garland, “Simultaneous determination of several crystal structures from powder mixtures: the combination of powder X-ray diffraction, band-target entropy minimization and Rietveld methods,” J. Appl. Crystallogr., vol. 47, no. 2, pp. 659–667, Apr. 2014, doi: 10.1107/S1600576714003379.
[25] S. Anandan, N. Ohashi, and M. Miyauchi, “ZnO-based visible-light photocatalyst: Band-gap engineering and
multi-electron reduction by co-catalyst,” Appl. Catal. B Environ., vol. 100, no. 3, pp. 502–509, Oct. 2010, doi: 10.1016/j.apcatb.2010.08.029.
[26] Y. M. Manawi, Ihsanullah, A. Samara, T. Al-Ansari, and M. A. Atieh, “A Review of Carbon Nanomaterials’ Synthesis via the Chemical Vapor Deposition (CVD) Method,” Materials, vol. 11, no. 5, p. 822, May 2018, doi: 10.3390/ma11050822.
[27] Moustafa. E. Elsisi, M. M. Mostafa, H. Abdella, A. E. Khalil, and A. S. Soror, “In-depth investigation the size effect of zinc oxide nanostructures on the photodegradation of different dyes under UV-irradiation: anticancer application,” Sci. Rep., vol. 15, no. 1, p. 31669, Aug. 2025, doi: 10.1038/s41598-025-16270-4.
[28] D. Atta, H. A. Wahab, M. A. Ibrahim, and I. K. Battisha, “Photocatalytic degradation of methylene blue dye by ZnO nanoparticle thin films, using Sol–gel technique and UV laser irradiation,” Sci. Rep., vol. 14, no. 1, p. 26961, Nov. 2024, doi: 10.1038/s41598-024-76938-1.
[29] N. Fathy, S. Fathy, F. Ali, and S. Mousa, “Effective sunlight photodegradation of methylene blue dye using zinc oxide doped with mono- and bi-metals of Ag and Ce,” Desalination Water Treat., vol. 320, p. 100595, Oct. 2024, doi: 10.1016/j.dwt.2024.100595.
[30] W. Vallejo, A. Cantillo, and C. Díaz-Uribe, “Methylene Blue Photodegradation under Visible Irradiation on Ag-Doped ZnO Thin Films,” Int. J. Photoenergy, vol. 2020, pp. 1–11, Jan. 2020, doi: 10.1155/2020/1627498.
[31] P. Eswaran, P. D. Madasamy, K. Pillay, and H. Brink, “Sunlight-driven photocatalytic degradation of methylene blue using ZnO/biochar nanocomposite derived from banana peels,” Biomass Convers. Biorefinery, vol. 15, no. 8, pp. 12347–12367, Apr. 2025, doi: 10.1007/s13399-024-05999-z.
[32] K. A. Isai and V. S. Shrivastava, “Photocatalytic degradation of methylene blue using ZnO and 2%Fe–ZnO semiconductor nanomaterials synthesized by sol–gel method: a comparative study,” SN Appl. Sci., vol. 1, no. 10, p. 1247, Oct. 2019, doi: 10.1007/s42452-019-1279-5.
DOI: https://doi.org/10.18860/al.v14i1.40636
Refbacks
- There are currently no refbacks.
Copyright (c) 2026 Maria Luruk Seran, Matius Stefanus Batu, Cindy Claudia Christanti, Didi Prasetyo Benu

This work is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License.
This work is licensed under NME Creative Commons Atribusi-NonKomersial-BerbagiSerupa 4.0 Internasional.
ALCHEMY is managed by http://kimia.uin-malang.ac.id/
© All rights reserved 2016. Alchemy, Journal of Chemistry, eISSN 2460-6871
View My Stats
