Co-deposition of CuO:ZnO Nanocomposite on n-Type Si Substrate by Chemical Bath Deposition (CBD) Technique for Photovoltaic Application

Abstract

In the present study, CuO:ZnO nanocomposite (NC)-based heterojunction photovoltaic devices have been successfully fabricated on n-type Si (<100>) wafers, utilizing a simple and cost-efficient chemical bath deposition (CBD) method. The primary focus of our research was to explore the optimal weight percentage of the co-deposited CuO and ZnO in the NCs and to investigate their material, chemical, and electronic properties. For this purpose, the synthesis processes were conducted with different stoichiometric ratios of CuO and ZnO, namely 1:2, 1:1, and 2:1, which we designated as CZ1, CZ2, and CZ3, respectively. The material properties of the fabricated devices were extensively studied with a synergetic approach of relevant experimental techniques, including field-emission scanning electron microscopy (FESEM), energy dispersive x-ray spectroscopy (EDX), and x-ray diffraction (XRD) measurements. A bandgap variation from 2.0 eV to 2.52 eV was measured for the samples using spectroscopic ellipsometry. Electrochemical impedance spectroscopy (EIS) analysis revealed that the CZ2 sample exhibited ~ 32% enhancement in recombination resistance in comparison to CZ1, indicating a reduction in non-radiative recombination at its heterointerface. Comparative photovoltaic analysis indicates that the highest efficiency of ~ 1.3% was achieved for the CZ2 device due to its superior crystalline quality, relatively higher absorbance in the visible region, and fewer interfacial defects. Therefore, this study explores the CBD technique for analyzing electronic and optoelectronic properties of the dual-oxide-based nanocomposite for its possible photovoltaic applications.