OICC Press Journal of Theoretical and Applied Physics 2251-7235 19 5 2025 09 30 Cost effective copper oxide thin layers by highly controlled spray pyrolysis method for optoelectronic devices 10.57647/j.jtap.2025.1905.46 EN Nardjes Randa Hamdaoui LPCMME Lab, Faculty of Exacte and applied Sciences, University Oran 1 Ahmed Ben Bella, 31000 Oran, Algeria Boussaada Salah Eddine Faculty of Exacte Sciences, Mustapha Stambouli Mascara University, 29000 Mascara, Algeria https://orcid.org/0009-0006-2540-3326 Younes Hammoudi Faculty of Exacte Sciences, Mustapha Stambouli Mascara University, 29000 Mascara, Algeria Lamia Barkat LPCMME Lab, Faculty of Exacte and applied Sciences, University Oran 1 Ahmed Ben Bella, 31000 Oran, Algeria Abdelbacet Khelil LPCMME Lab, Faculty of Exacte and applied Sciences, University Oran 1 Ahmed Ben Bella, 31000 Oran, Algeria Cristina Bogatu Auricia Center for Renewable Energy System and Recycling, R&D Institute of the Transilvania University of Brasov, Eroilor 29 Street, 500036, Brasov, Romania Dana Perniu Center for Renewable Energy System and Recycling, R&D Institute of the Transilvania University of Brasov, Eroilor 29 Street, 500036, Brasov, Romania Anca Duta Center for Renewable Energy System and Recycling, R&D Institute of the Transilvania University of Brasov, Eroilor 29 Street, 500036, Brasov, Romania Younes Mouchaal LPCMME Lab, Faculty of Exacte and applied Sciences, University Oran 1 Ahmed Ben Bella, 31000 Oran, Algeria; Faculty of Exacte Sciences, Mustapha Stambouli Mascara University, 29000 Mascara, Algeria Journal Article 2025 09 30 Copper Oxide (CuO) thin films were deposited via spray pyrolysis, and the effect of precursor concentration on their structural, morphological, optical, and electrical properties was systematically investigated. X-ray diffraction confirmed a monoclinic crystal structure with optimal crystallinity at 0.06 M, yielding a crystallite size of 25.27 nm. SEM and AFM analyses revealed improved surface uniformity, larger grains, and reduced defects at this concentration. The optimized films exhibited 63% average transmittance in the visible range and an optical bandgap between 1.53 and 2.10 eV. These results demonstrate that cost-effective CuO thin films can achieve properties comparable to those of metal oxides produced by more expensive techniques, positioning them as promising candidates for optoelectronic and photovoltaic applications.