Preparing Cu₂ZnSnS₄ films using the co-electro-deposition method with ionic liquids

Cu₂ZnSnS₄ (CZTS) films are successfully prepared by co-electrodeposition in aqueous ionic solution and sulfurized in elemental sulfur vapor ambient at 400℃ for 30 min using nitrogen as the protective gas. It is found that the CZTS film synthesized at Cu/(Zn+Sn)=0.71 has a kesterite structure, a bandgap of about 1.51 eV, and an absorption coefficient of the order of 10⁴ cm^-1. This indicates that the co-electrodeposition method with aqueous ionic solution is a viable process for the growth of CZTS films for application in photovoltaic devices.