Luong Hoai Nhon, Nguyen Huu Khoa, Lai Thi Ngoc Huyen, Huynh Hung Quang, Dinh Tan Muon, Nguyen Ngoc Phuong, Tran Cong Khanh, Phan Bach Thang, Dang Vinh Quang

Main Article Content

Abstract

ZnO is a promising photocatalyst for photocatalytic oxidation of organic compounds under the influence of sunlight that provides clean energy and decomposes sustainable organic pollutants substances. ZnO is found to have non-toxic properties, long-term stability, high carrier mobility, low cost and biocompatibility. However, some disadvantages of ZnO limit its use in photocatalysis. Due to its wide bandgap, ZnO can only be activated under UV illumination. On the other hand, the photo-excited electron-hole pairs that recombine quickly on ZnO surface, suppress its photocatalytic properties. To improve its properties and performance, doping with transition metals was used to improve the optical properties of ZnO. Among the transition metal ions, Manganese (Mn) was commonly used to improve and tune the optical, electrical, diameter, height, and the number of nanorods (NRs) per unit area. Introduction of Mn into ZnO could enhance the photocatalytic activity due to the increase in the defect sites that effectively decreased the recombination of free electrons and holes. This study successfully synthesized ZnO nanorod arrays generated on glass substrates with different concentrations of doping Mn (0, 0.5, 1, 1.5 and 2%) at 100 °C by a simple hydrothermal method. To investigate the structure, morphology and optical properties, ultraviolet-visible spectroscopy (UV-Vis), X-ray diffraction (XRD) and scanning electron microscopy (SEM) were conducted. With the range of Mn doping ≤ 2% mol, the band gap reduced slightly, and the most optimized Mn doping concentration was of 0.5%. Overall, this work shows that the most effective way to increase ZnO’s photocatalytic activity in the visible region by reducing its band gap was the reduction in the size of the material or denaturation of ZnO by certain metals or non-metals.


 

Keywords: ZnO NRs, doping, photocatalyst, visible light, methylene blu.

References

[1] J. Liqiang, F. Honggang, W. Baiqi, W. Dejun, X. Baifu, L. Shudan, S. Jiazhong, Effects of Sn Dopant on the Photoinduced Charge Property and Photocatalytic Activity of TiO2 Nanoparticles, Applied Catalysis B: Environmental, Vol. 62, No. 3, 2006, pp. 282-291, https://doi.org/10.1016/j.apcatb.2005.08.012.
[2] G. Cai, L. Xu, B. Wei, J. Che, H. Gao, W. Sun, Facile Synthesis of β-Bi2O3/Bi2O2CO3 Nanocomposite with High Visible-light Photocatalytic Activity, Materials Letters, Vol. 120, 2014, pp. 1-4, https://doi.org/10.1016/j.matlet.2014.01.027.
[3] Z. Muslim, K. Aadim, R. Kadhim, Preparation of ZnO for Photocatalytic Activity of Methylene Blue Dye, International Journal of Basic and Applied Science, Vol. 6, No. 1, 2017, pp. 1-7, https://doi.org/10.17142/ijbas-2017.6.1.1.
[4] Ü. Özgür, Y. I. Alivov, C. Liu, A. Teke, M. A. Reshchikov, S. Doğan, V. Avrutin, S. J. Cho, H. Morkoç,
A Comprehensive Review of ZnO materials and Devices, Journal of Applied Physics, Vol. 98, No. 4, 2005,
pp. 041301, https://doi.org/10.1063/1.1992666.
[5] F. Achouri, S. Corbel, L. Balan, K. Mozet, E. Girot, G. Medjahdi, M. B. Said, A. Ghrabi, R. Schneider, Porous Mn-doped ZnO Nanoparticles for Enhanced Solar and Visible Light Photocatalysis, Materials & Design. C,
Vol. 101, 2016, pp. 309-316, https://doi.org/10.1016/j.matdes.2016.04.015.
[6] S. Anandan, A. Vinu, T. Mori, N. Gokulakrishnan, P. Srinivasu, V. Murugesan, K. Ariga, Photocatalytic Degradation of 2,4,6-trichlorophenol using Lanthanum Doped ZnO in Aqueous Suspension, Catalysis Communications - CATAL COMMUN, Vol. 8, No. 9 2007, pp. 1377-1382, https://doi.org/10.1016/j.catcom.2006.12.001.
[7] S. A. Ahmed, Structural, Optical, and Magnetic Properties of Mn-doped ZnO Samples, Results in Physics, Vol. 7, 2017, pp. 604-610, https://doi.org/10.1016/j.rinp.2017.01.018.
[8] R. Saleh, N. F. Djaja, Transition-metal-doped ZnO Nanoparticles: Synthesis, Characterization and Photocatalytic Activity under UV Light, Spectrochim Acta A Mol Biomol Spectrosc, Vol. 130, 2014, pp. 581-590, https://doi.org/10.1016/j.saa.2014.03.089.
[9] N. Verma, S. Bhatia, R. K. Bedi, Sn-doped ZnO Nanopetal Networks for Efficient Photocatalytic Degradation of Dye and Gas Sensing Applications, Applied Surface Science, Vol. 407, 2017, pp. 495-502, https://doi.org/10.1016/j.apsusc.2017.02.205.
[10] A. Tabib, W. Bouslama, B. Sieber, A. Addad, H. Elhouichet, M. Férid, R. Boukherroub, Structural and optical Properties of Na Doped ZnO Nanocrystals: Application to Solar Photocatalysis, Applied Surface Science,
Vol. 396, 2017, pp. 1528-1538, https://doi.org/10.1016/j.apsusc.2016.11.204.
[11] A. Kadam, D. D. Bhopate, V. Kondalkar, S. Majhi, C. Bathula, A. V. Tran, S. W. Lee, Facile Synthesis of Ag-ZnO Core–shell Nanostructures with Enhanced Photocatalytic Activity, Journal of Industrial and Engineering Chemistry, Vol. 107, 2017, pp. 2411-2502, https://doi.org/10.1016/j.jiec.2017.12.003.
[12] N. Kamarulzaman, M. F. Kasim, R. Rusdi, Band Gap Narrowing and Widening of ZnO Nanostructures and Doped Materials, Nanoscale Research Letters, Vol. 10, No. 1, 2015, pp. 346, https://doi.org/10.1186/s11671-015-1034-9.
[13] A. S. Hameed, C. Karthikeyan, S. Sasikumar, V. S. Kumar, G. Ravi, Impact of Alkaline Metal Ions Mg2+, Ca2+, Sr2+ and Ba2+ on the Structural, Optical, Thermal and Antibacterial Properties of ZnO Nanoparticles Prepared by the Co-Precipitation Method, Journal of Materials Chemistry B, Vol. 1, No. 43, 2021, pp. 5950-5962, http://doi.org/ 10.1039/C3TB21068E.
[14] D. Appell, Nanotechnology, Wired for Success, Nature, Vol. 419, No. 6907, 2002, pp. 553-555, https://doi.org/10.1038/419553a.
[15] D. P. Joseph, C. Venkateswaran, Bandgap Engineering in ZnO By Doping with 3d Transition Metal Ions, Journal of Atomic and Molecular Physics, Vol. 2011, 2011, pp. e270540, https://doi.org/10.1155/2011/270540.
[16] N. A. Putri, V. Fauzia, S. Iwan, L. Roza, A. A. Umar, S. Budi, Mn-doping-induced Photocatalytic Activity Enhancement of ZnO Nanorods Prepared on Glass Substrates, Applied Surface Science, Vol. 439, 2018,
pp. 285-297, https://doi.org/10.1016/j.apsusc.2017.12.246.
[17] N. Rajamanickam, S. Rajashabala, K. Ramachandran, Effect of Mn-doping on the Structural, Morphological and Optical Properties of ZnO Nanorods, Superlattices and Microstructures, Vol. 65, 2014, pp. 240-247, https://doi.org/10.1016/j.spmi.2013.11.005.
[18] S. Senthilkumaar, K. Rajendran, S. Banerjee, T. K. Chini, V. Sengodan, Influence of Mn Doping on the Microstructure and Optical Property of ZnO, Materials Science in Semiconductor Processing, Vol. 11, No. 1, 2008, pp. 6-12, https://doi.org/10.1016/j.mssp.2008.04.005.
[19] J. Du, Z. Liu, Y. Huang, Y. Gao, B. Han, W. Li, G. Yang, Control of ZnO Morphologies Via Surfactants Assisted Route in the Subcritical Water, Journal of Crystal Growth, Vol. 280, No. 1-2, 2005, pp. 126-134, https://doi.org/10.1016/j.jcrysgro.2005.03.006.
[20] M. Yilmaz, Ş. Aydoğan, The Effect of Mn Incorporation on the Structural, Morphological, Optical, and Electrical Features of Nanocrystalline ZnO Thin Films Prepared by Chemical Spray Pyrolysis Technique, Metallurgical and Materials Transactions A, Vol. 46, No. 6, 2015, pp. 2726-2735, https://doi.org/10.1007/s11661-015-2875-7.
[21] W. Li, G. Wang, C. Chen, J. Liao, Z. Li, Enhanced Visible Light Photocatalytic Activity of ZnO Nanowires Doped with Mn2+ and Co2+ Ions, Nanomaterials (Basel), Vol. 7, No. 1, 2017, pp. E20, https://doi.org/10.3390/nano7010020.
[22] B. Panigrahy, M. Aslam, D. Bahadur, Aqueous Synthesis of Mn- and Co-Doped ZnO Nanorods, J. Phys. Chem. C, Vol. 114, No. 27, 2010, pp. 11758-11763, https://doi.org/10.1021/jp102163b.
[23] U. Holzwarth, N. Gibson, The Scherrer Equation Versus the “Debye-Scherrer equation,” Nature Nanotech,
Vol. 6, 2011, pp. 534-534, https://doi.org/10.1038/nnano.2011.145.
[24] Q. Ma, X. Lv, Y. Wang, J. Chen, Optical and Photocatalytic Properties of Mn Doped Flower-like ZnO Hierarchical Structures, Optical Materials, Vol. C, 2016, pp. 86-93, https://doi.org/10.1016/j.optmat.2016.07.014.
[25] M. V. Gallegos, M. A. Peluso, H. Thomas, L. C. Damonte, J. E. Sambeth, Structural and Optical Properties of ZnO and Manganese-doped ZnO, Journal of Alloys and Compounds, Vol. 689, 2016, pp. 416-424, https://doi.org/10.1016/j.jallcom.2016.07.283.
[26] Ş. Ş. Türkyılmaz, N. Güy, M. Özacar, Photocatalytic Efficiencies of Ni, Mn, Fe and Ag Doped ZnO Nanostructures Synthesized by Hydrothermal Method: The Synergistic/Antagonistic Effect between ZnO and Metals, Journal of Photochemistry and Photobiology A: Chemistry, Vol. 341, 2017, pp. 39-50, https://doi.org/10.1016/j.jphotochem.2017.03.027.
[27] V. V. Strelchuk, A. S. Nikolenko, O. F. Kolomys, S. V. Rarata, K. A. Avramenko, Р. М. Lytvyn, P. Tronc,
C. O. Chey, O. Nur, M. Willander, Optical and Structural Properties of Mn-doped ZnO Nanorods Grown by Aqueous Chemical Growth for Spintronic Applications, Thin Solid Films, Vol. 601, 2016, pp. 22-27, https://doi.org/10.1016/j.tsf.2015.11.019.
[28] P. Singh, A. Kaushal, D. Kaur, Mn-doped ZnO Nanocrystalline thin Films Prepared by Ultrasonic Spray Pyrolysis, Journal of Alloys and Compounds, Vol. 471, No. 1-2, 2009, pp. 11-15, https://doi.org/10.1016/j.jallcom.2008.03.123.
[29] L. C. Chen, C. H. Tien, C. S. Fu, Magneto-optical Characteristics of Mn-doped ZnO Films Deposited by Ultrasonic Spray Pyrolysis, Materials Science in Semiconductor Processing, Vol. 15, No. 1, 2012, pp. 80-85, https://doi.org/10.1016/j.mssp.2011.04.003.
[30] M. M. Cortalezzi, J. Rose, E. Tsui, A.R. Barron, J. Y. Bottero, M. Wiesner, Synthesis and Characterization of Manganese Doped Ferroxane Nanoparticles, MRS Proceedings, Vol. 800, 2003, pp. 27-32, https://doi.org/10.1557/PROC-800-AA9.4.
[31] R. Ullah, J. Dutta, Photocatalytic Degradation of Organic Dyes with Manganese-doped ZnO Nanoparticles, Journal of Hazardous Materials, Vol. 156, No. 1, 2008, pp. 194-200, https://doi.org/10.1016/j.jhazmat.2007.12.033.
[32] R. Viswanatha, S. Sapra, S. Sen Gupta, B. Satpati, P. V. Satyam, B. N. Dev, D. D. Sarma, Synthesis and Characterization of Mn-Doped ZnO Nanocrystals, J. Phys. Chem. B, Vol. 108, 2004, pp. 6303-6310, https://doi.org/10.1021/jp049960o.
[33] Z. B. Bahşi, A. Y. Oral, Effects of Mn and Cu Doping on the Microstructures and Optical Properties of Sol-Gel Derived ZnO thin Films, Optical Materials, Vol. 29, 2007, pp. 672-678, https://doi.org/10.1016/j.optmat.2005.11.016.
[34] U. N. Maiti, P. K. Ghosh, S. Nandy, K. K. Chattopadhyay, Effect of Mn Doping on the Optical and Structural Properties of ZnO Nano/micro-fibrous thin Film Synthesized by Sol–gel Technique, Physica B: Condensed Matter, Vol. 387, No. 1, 2007, pp. 103-108, https://doi.org/10.1016/j.physb.2006.03.090.
[35] Z. B. Bahşi, A. Y. Oral, Effects of Mn and Cu Doping On The Microstructures And Optical Properties of Sol–Gel Derived ZnO thin Films, Optical Materials, Vol. 29, 2007, pp. 672-678, https://doi.org/10.1016/j.optmat.2005.11.016.
[36] M. Samadi, M. Zirak, A. Naseri, E. Khorashadizade, A. Z. Moshfegh, Recent Progress on Doped ZnO Nanostructures for Visible-light Photocatalysis, thin Solid Films, Vol. 387, No. 1, 2007, pp. 103-108, https://doi.org/10.1016/j.tsf.2015.12.064.
[37] D. K. Dubey, D. N. Singh, S. Kumar, C. Nayak, P. Kumbhakar, S. N. Jha, D. Bhattacharya, A. K. Ghosh,
S. Chatterjee, Local Structure and Photocatalytic Properties of Sol-gel Derived Mn–Li Co-doped ZnO Diluted Magnetic Semiconductor Nanocrystals, RSC Advances, Vol 6, 2016, pp. 22852-22867, https://doi.org/10.1039/C5RA23220A.
[38] B. Donkova, D. Dimitrov, M. Kostadinov, E. Mitkova, D. Mehandjiev, Catalytic and Photocatalytic Activity of Lightly Doped Catalysts M:ZnO (M=Cu, Mn), Materials Chemistry and Physics, Vol. 123, No. 2, 2010,
pp. 563-568, https://doi.org/10.1016/j.matchemphys.2010.05.015.
[39] 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, Vol. 81, 2018, pp. 536-551, https://doi.org/10.1016/j.rser.2017.08.020.
[40] C. Van, H. Nguyen, H. Huynh, H. Pham, T. Dinh, H. Luong, B. Phan, C. Tran, V. Dang, Multi-modification of ZnO Nanorods to Enhance the Visible Absorption, Advances in Natural Sciences: Nanoscience and Nanotechnology, Vol. 11, No. 1, 2020, pp. 015002, https://doi.org/10.1088/2043-6254/ab6290.
[41] H. N. Pham, M. H. Tong, H. Q. Huynh, H. D. Phan, C. K. Tran, B. T. Phan, V. Q. Dang, The Enhancement of Visible Photodetector Performance based on Mn-doped ZnO Nanorods by Substrate Architecting, Sensors and Actuators A: Physical, Vol. 311, 2020, pp. 112085, https://doi.org/10.1016/j.sna.2020.112085.