Impact of Chemical Source Selection on Aqueous Spray-Deposited CZTSSe Solar Cells

The quest for a simple and cost-effective fabrication process to achieve high power conversion efficiency (PCE) in Cu2ZnSn(S,Se)4 (CZTSSe) solar cells has become increasingly important. Aqueous spray deposition is a promising method for the production of environmentally friendly and economically viable thin-film solar cells. In this study, we investigated the use of acetate, nitrate, and chloride sources in the aqueous spray deposition of CZTSSe. The effect of these chemical sources on the opto-electric and defect properties of the resulting thin films was thoroughly analyzed. Results showed that the acetate source resulted in high defect densities and a significant number of CuZn antisites, while the use of nitrate and chloride sources improved solution stability and performance of the CZTSSe solar cells. The chloride-based solution was found to be the most stable, offering a unique opportunity for a reusable and cost-effective fabrication process. This study highlights the importance of chemical source selection in aqueous fabrication for the production of high-quality CZTSSe solar cells.