Experimental and Simulation Study of Co₃O₄ Thin Films: Impact of Nickel Concentration on Physical Properties and Photovoltaic Performance

Abstract Nickel‐doped absorbing layers on glass substrates are successfully fabricated using the spray pyrolysis technique, significantly enhancing the efficiency of the multi‐layer solar cell structured as SLG/Mo/ Ni/ZnS/ITO/Al. The results demonstrate the impact of Ni doping on the structural, morphological, and optical properties of X‐ray diffraction (XRD) and Raman spectroscopy confirm the formation of a cubic spinel structure in the films, with crystallite sizes ranging from 11.89 to 13.11 nm. Scanning electron microscope (SEM) images reveal nearly homogeneous surfaces with enhanced porous morphology, attributed to varying dopant percentages. Energy‐dispersive X‐ray spectroscopy (EDX) confirms the presence of Co, O, and Ni in the films. UV–vis spectrophotometry shows improved absorbance, with the 2% Ni‐doped sample identified as optimal. SCAPS‐1D simulations based on these experimental results indicate an overall solar cell efficiency increase to 9.89% for the 2% Ni‐doped films.