Effect of Different Annealing Temperatures on Structural, Optical, Morphological and Electrical Properties of Cu - ZnO Thin Films Prepared Using Sol—gel Spin Coating Techniques

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Mohana F. Attia


In this study, Cu - doped ZnO thin films were prepared at different annealing temperatures from Copper acetate precursor by sol-gel spin coating method for Photocatalytic Applications.  The films were characterized by X-ray diffractometer (XRD), scanning electron microscopy (SEM), and Fourier transform infrared spectroscopy (FTIR).  The obtained powders were annealed under air in the range of  for Cu – ZnO. The surface morphological, structural, electrical and optical properties of the as-deposited ZnO films have been investigated as a function of Cu-doping level.  The thickness of the films was estimated by Fizeau fringes interference method which varied from 195 to 198 nm. The X-ray diffraction analysis indicated that the wurtzite structure was maintained for all samples and copper was successfully doped into ZnO at low TC. However, the formation of monoclinic CuO was observed at higher TC. For Cu – ZnO, the crystallite size increased with the annealing temperature from 15.86 to 24.24 nm. The isotherms obtained were type IV with a hysteresis type H 3, confirming the mesoporous behavior of the catalysts. The surface area was in the range of 35.1 to 8.66 /g. All the prepared catalysts mainly showed two emission regions: a sharp peak in the ultraviolet region and another broad peak in the visible region. The photocatalytic activity was achieved by the degradation of 300 mg/L malachite green (MG) aqueous solution under UV irradiation. The findings showed that the increased annealing of different concentration of Cu doped ZnO with CuO on the surface resulted in highly improved photocatalytic activity. Various optical constants such as absorbance, transmittance of the films have been studied. The values of transmittance are high in the visible and IR region and it is minimum in the UV region. Absorbance decreases with higher percentage of Cu concentration. The band gap of the films varied 3.21 to 3.05 eV. The resistivity gradually decreases with the increase of temperature, which indicates the semiconducting nature of the materials. Resistivity also increases with the increasing doping concentration. The conductivity decreases with the increasing of Cu concentration.

Zinc oxide, sol – gel, malachite green, annealing temperature, copper, photocatalytic activity, resistivity, conductivity

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Attia, M. F. (2019). Effect of Different Annealing Temperatures on Structural, Optical, Morphological and Electrical Properties of Cu - ZnO Thin Films Prepared Using Sol—gel Spin Coating Techniques. Journal of Materials Science Research and Reviews, 3(2), 1-25. Retrieved from http://journaljmsrr.com/index.php/JMSRR/article/view/30089
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Kavitha T, Yuvaraj H. A facile approach to the synthesis of high-quality NiO nanorods: Electrochemical and antibacterial properties. J. Mater. Chem. 2011;21: 15686-15691.

DOI: 10.1039/C1JM13278D

Wu CC, Shih WC. Development of a highly transparent, low-resistance lithium-doped nickel oxide triple-layer film deposited by magnetron sputtering. Chem. Commun. 2017;53:1634–1637.

DOI: 10.1039/C6CC08738H

Karali T, Can N, Valberg L, Stepanov AL, Townsend PD, Buchal Ch., Ganeev RA, Ryasnyansky AI, Belik HG, Jessett ML, Ong C. Optical properties and luminescence of metallic nanoclusters in ZnO: Cu. Physica B: Condensed Matter. 2005;363:88-95. doi.org/10.1016/j.physb.2005.03.006

Vikas Sharma, Inderjeet Singh, Amreesh Chandra. Hollow nanostructures of metal oxides as next generation electrode materials for supercapacitors. Scientific Reports. 2018;8. Article number: 1307. doi.org/10.1038/s41598-018-19815-y

Khan Mamun Reza, Kurny ASW, Fahmida Gulshan. Parameters affecting the photocatalytic degradation of dyes using TiO2: A review. Applied Water Science. 2017;7(4):1569–1578. Available:https://link.springer.com/article/10.1007/s13201-015-0367-y

El-Hilo M, Dakhel AA, Ali-Mohamed AY. Room temperature ferromagnetism in Nanocrystalline Ni-doped ZnO synthesized by co-precipitation. Journal of Magnetism and Magnetic Materials. 2009;321:2279–2283.


Mamat MH, Sahdan MZ, Khusaimi Z, Zain Ahmed A, Abdullah S, Rusop M. Influence of doping concentrations on the aluminum doped zinc oxide thin films properties for ultraviolet photoconductive sensor applications. Optical Materials. 2010;32: 696–699. doi.org/10.1016/j.optmat.2009.12.005

Li JH, Liu YC, Shao CL, Zhang XT, Shen DZ, Lu YM, Zhang JY, Fan XW. Effects of thermal annealing on the structural and optical properties of Mgx Zn1−x O nanocrystals. J Colloid Interf Sci. 2005; 283:513-517.

DOI: 10.1016/j.jcis.2004.09.011

Krunks M, Dedova T, Açik IO. Spray pyrolysis deposition of zinc oxide nanostructured layers. Thin Solid Films. 2006;515:1157-1160. doi.org/10.1016/j.tsf.2006.07.134

Ramakrishna Murthy M, Venkateshwar Rao E. Ion-beam modifications of the surface morphology and conductivity in some polymer thin films. Bulletin of Materials Science. 2002;25:403–406. doi.org/10.1007/BF02708018

Abdelrahman MM, Osman M, Hashhash A. Electrical properties of irradiated PVA film by using ion/electron beam. Progress of Theoretical and Experimental Physics; 2016.


Fekete ZA, Wilusz E, Karasz FE, Visy C. Ion beam irradiation of conjugated polymers for preparing new membrane materials-A theoretical study. Separation Purification Technology. 2007;57:440– 443.


Makuuchi K, Cheng S. Radiation processing of polymer materials and its industrial applications. (Copyright © 2012 John Wiley & Sons, Inc.). Online

ISBN: 9781118162798.


Sahbeni K, et al. Annealing temperature effect on the physical properties of titanium oxide thin films prepared by the sol-gel method. Journal of Physical Chemistry & Biophysics. 2017;7:257.


Abdolahzadeh Ziabari A, Ghodsi FE. Optical and Structural Studies of Sol-Gel Deposited Nanostructured CdO Thin Films: annealing effect. ACTA Physica Polonica A. 2011; 120.


Agawane GL, Shin SW, Vanalaka SA, Jin Hyeok Kim. Synthesis of simple, low cost and benign sol–gel Cu2ZnSnS4 thin films: influence of different annealing atmospheres. J Mater Sci: Mater Electron. 2015;26:1900–1907.

DOI: 10.1007/s10854-014-2627-2

Kai Loong Foo, Uda Hashim, Kashif Muhammad, Chun Hong Voon. Sol–gel synthesized zinc oxide nanorods and their structural and optical investigation for optoelectronic application. Nanoscale Res Lett. 2014;9.

DOI: 10.1186/1556-276X-9-429

Özgür Ü, et al. A comprehensive review of ZnO materials and devices. J. Appl. Phys. 2005;98:041301-103. Available:https://doi.org/10.1063/1.1992666

Vinod Kumar, et al. Rare earth doped zinc oxide nanophosphor powder: A future material for solid state lighting and solar cells. ACS Photonics. 2017;4(11):2613-2637. Available:https://10.1021/acsphotonics.7b00777

Vinod Kumar, et al. Synthesis and characterization of aluminum–boron co-doped ZnO nanostructures. Material Research Bulletin. 2013;48:362.


Rabia Qindeel, et al. Characterizations of multilayer ZnO thin films deposited by sol-gel spin coating technique. Results in Physics. 2017;7:651-655.


Amari R, et al. Structural, optical and luminescence properties of ZnO thin films prepared by sol-gel spin-coating method: Effect of precursor concentration. CHIN. PHYS. LETT. 2018;35(1):01680.


Vinod Kumar, et al. Deep level defect correlated emission and Si diffusion in ZnO: Tb3+ thin films prepared by pulsed laser deposition. J. Colloid and Interface Science. 2016;465:295.


Kaniz Naila Tonny, et al. Electrical, optical and structural properties of transparent conducting Al doped ZnO (AZO) deposited by sol-gel spin coating. AIP Advances. 2018;8:065307. Available:https://doi.org/10.1063/1.5023020

Ziaul Raza Khan. Sol-gel derived Cds nanocrystalline thin films: Optical and photoconduction properties. Materials Science-Poland. 2018;36(2):235–241. Available:https://doi.org/10.1515/msp-2018-0028

Sugi S, Usha Rajalakshmi, Shanthi J. Photocatalytic degradation Efficiency of CuXZn1-XO composite. Optik. 2017;131: 406-413. doi.org/10.1016/j.ijleo.2016.11.030

Marco Laurenti, Valentina Cauda. Porous zinc oxide thin films: Synthesis approaches and applications. MDPI Coatings. 2018; 8(2):67.


Kadam LD, Patil PS. Thickness-dependent properties of sprayed cobalt oxide thin films. Materials Chemistry and Physics. 2001;68:225–232. Available:https://doi:10.1016/s0254-0584(00)00367-9

Hashim H, et al. Investigation of annealing temperature on copper oxide thin films using sol-gel spin coating technique. IOP Conference Series Materials Science and Engineering. 2018;340(1):012008.


Tolansky S. Multiple beam interferometry of surface and films. Oxford University Press, London; 1948.

Muniz FTL, Miranda MAR, Morilla dos Santos C, Sasaki JM. The Scherrer equation and the dynamical theory of X-ray diffraction. Acta Crystallographica Section A. 2016;A72:385-390.


Sharma RK, Patel S, Pargaien KC. Synthesis, characterization and properties of Mn-doped ZnO nanocrystals. Advances in Natural Sciences: Nanoscience and Nanotechnology. 2012;3(3):035005.


Triloki, Garg P, Rai R, Singh BK. Structural characterization of “as-deposited” cesium iodide films studied by X-ray diffraction and transmission electron microscopy techniques. Cond-Mat. Mtrl-Sci. 2013; arXiv:1211.5540v3.

Alessio Becheri, Maximilian Dürr, Pierandrea Lo Nostro, Piero Baglioni. Synthesis and characterization of zinc oxide nanoparticles: Application to textiles as UV-absorbers. 2008;10:679–689.


Muthukumaran S, Gopalakrishnan R. Structural, FTIR and photoluminescence studies of Cu doped ZnO nanopowders by co-precipitation method. Opt. Mater. 2012; 34:1946–1953. doi.org/10.1016/j.optmat.2012.06.004

Xiong G, Luo L, Li C, Yang X. Synthesis of mesoporous ZnO (m-ZnO) and catalytic performance of the Pd/m-ZnO catalyst for methanol steam reforming. Energy & Fuels. 2009;23(3):1342–1346.


Hussein MZ, Al Ali SH, Zainal Z, Hakim MN. Development of antiproliferative nanohybrid compound with controlled release property using ellagic acid as the active agent. International Journal of Nanomedicine. 2011;6(1):1373–1383.


Xiong G, Luo L, Li C, Yang X. Synthesis of mesoporous ZnO (m-ZnO) and catalytic performance of the Pd/m-ZnO catalyst for methanol steam reforming. Energy & Fuels. 2009;23(3):1342–1346.


Dhamodharan P, Gobi R, Shanmugam N, Kannadasan N, Poonguzhali R, Ramya S. Synthesis and characterization of surfactants assisted Cu2+doped ZnO nanocrystals. Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy. 2014;131:125–131. doi.org/10.1016/j.saa.2014.04.083.

Modwi A, Abbo MA, Hassan EA, Ammar Houas. Adsorption kinetic and photocatalytic degradation of malachite green (MG) via Cu/ZnO nanocomposites. Journal of Environmental Chemical Engineering. 2017;5:5954–5960.


Jongnavakit P, Amornpitoksuk P, Suwanboon S, Ndiege N. Preparation and photocatalytic activity of Cu-doped ZnO thin films prepared by the sol–gel method. Appl. Surf. Sci. 2012;258:8192–8198.


Ghiloufi I, Ghoul J. El, Modwi A, Mir L. El. Ga-doped ZnO for adsorption of heavy metals from aqueous solution. Materials Science in Semiconductor Processing. 2016;42(3):102–106. Available:http://doi:10.1016/j.mssp.2015.08.047

Oskoei V, Dehghani MH, Nazmara S, Heibati B, Asif M, Tyagi I, Gupta VK. Removal of humic acid from aqueous solution using UV/ZnO nano-photocatalysis and adsorption. Journal of Molecular Liquids. 2015;213:374–380.


Ayeshamariam A, et al. Synthesis and characterization of ZnO–CuO nanocomposites powder by modified perfume spray pyrolysis method and its antimicrobial investigation. Journal of Semiconductors. 2018;39(3):033001.


Kaviyarasu K, et al. Synthesis and characterization studies of MgO: CuO nanocrystals by wet-chemical method. Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy. 2015;142: 405-409. Available:https://doi.org/10.1016/j.saa.2015.01.111

Subba Reddy Y, et al. Equilibrium and kinetic studies of the adsorption of acid blue 9 and Safranin O from aqueous solutions by MgO decked FLG coated Fuller's earth. Journal of Physics and Chemistry of Solids. 2018;123:43-51. Available:https://doi.org/10.1016/j.jpcs.2018.07.009

Lee HJ, Kim BS, Cho CR, Jeong SY. A study of magnetic and optical properties of Cu doped ZnO. Phys. Stat. Sol. 2004; 241(7):1533-1536. Available:https://doi.org/10.1002/pssb.200304614

Jongnavakit P, Amornpitoksuk P, Suwanboon S, Ndiege N. “Preparation and photocatalytic activity of Cu-doped ZnO thin films prepared by the sol–gel method. Applied Surface Science. 2012;258(20): 8192–8198. Available:https://doi:10.1016/j.apsusc.2012.05.021

Chauhan, Kumar A, Chaudhary RP. Structure and optical properties of Zn 1-X Ni X O nanoparticles by coprecipitation methodruby. Journal of Optoelectronics and Biomedical Materials. 2011;3(1):17-23. Available:https://10.1007/s11164-011-0478-5

Furdyna JK. Diluted magnetic semiconductors. Appl. Phys. 1988;64(4). Available:https://10.1063/1.341700

Zhang Y, Lin B, Fu Z, Liu C, Han W. Strong ultraviolet emission and rectifying behaviour of nanocrystalline ZnO films. Opt. Mater. 2006;28,1192–1196.


Gandhi V, Ganesan R, Hameed H, Syedahamed A, Thaiyan M. J. Phys. Chem. C. 2014;118:9715–9725.

Li P, Wang S, Li J, Wei Y. Structural and optical properties of Co- doped ZnO nanocrystallites prepared by a one-step solution route. Journal of Luminescence. 2012;132(1):220–225. Available:http://doi:10.1016/j.jlumin.2011.08.019

Xu DH, Shen WZ. Cu-doped ZnO hemispherical shell structures: Synthesis and room-temperature ferromagnetism properties. Journal of Physical Chemistry C. 2012;116(24):13368–13373.


Udayabhaskar R, Mangalaraja RV, Karthikeyan B. Thermal annealing induced structural and optical properties of Ca doped ZnO nanoparticles. Journal of Materials Science: Materials in Electronics. 2013;1–6.


Zotov AO, et al. Electrical conductivity of Cu/ZnO/Si heterostructures. IOP Conf. Series: Journal of Physics: Conf. Series. 2017;816:012013.