Colloidal CCTS nanoparticle synthesis by solution method for solar photovoltaic applications

Copper Cobalt Tin Sulfide (CCTS) is synthesized via simple and cost effective wet chemical method. CuCl2.2H2O, CoCl2·6H2O, SnCl2.5H2O and CH4N2S were blended in ethanol in definite ratios and the resulting colloidal solution is filtered to recover CCTS powder. Optical studies revealed a bandgap of 1.67 eV with high absorption coefficient of 2.5 × 105 cm−1. The phase formation of tetragonal crystal for CCTS as major composition with negligible secondary phases was confirmed using Raman spectroscopy. XPS indicated the valence of copper, cobalt, tin & sulfur as +1, +2, +4 & −2 respectively. As the present method of synthesis of CCTS is suitable to control secondary phases and formation of stable single phase, CCTS obtained by this method will be optimal for solar cell applications.