Sb2(SxSe1-x)3 thin films by electrodeposition: Role of deposition potential on the formation of the solid solution and photovoltaic performance via device simulation

This work presents one-step electrodeposition of antimony sulfide selenide (Sb2(SxSe1-x)3) thin films on fluorine doped SnO2 substrates. Based on the cyclic voltammetry studies the Sb2(SxSe1-x)3 absorber layers were deposited at different potentials in the range of-0.6 to-0.72 V vs. saturated calomel electrode. The deposited films were uniform and well adhered to the substrate. The effects of the deposition potential and the post-deposition annealing treatment on the physical and chemical properties of the films were analyzed using X-ray diffrac-tion (XRD), Raman spectroscopy, atomic force microscopy, scanning electron microscopy, and UV-visible-NIR spectroscopy. The films were crystallized in an orthorhombic crystal structure and the formation of ternary material without any impurity phases was clear from the XRD. The optical band gap of Sb2(SxSe1-x)3 decreased with the increase of the Se concentration in the films. The Mott Schottky plot showed negative slope charac-teristic of p-type materials. A larger carrier concentration was obtained for films deposited at more negative potentials due to their higher Se content. Solar cells modeled on experimental data of Sb2(SxSe1-x)3 thin films were investigated via device simulation using SCAPS-1D software. The FTO/Sb2(SxSe1-x)3/SnS2 structure showed an efficiency of 11.5%, demonstrating the feasibility of SnS2 as a cadmium-free alternative to the traditional CdS buffer layer.