Thin film solar cell using earth abundant Cu2SnS3 (CTS) fabricated through spray pyrolysis: Influence of precursors

This paper reports optimization and characterization of Cu2SnS3 (CTS) thin films prepared using simple and economical Chemical Spray Pyrolysis (CSP) technique. Effect of tin precursor (stannic/stannous chloride) on the structural, optical, electrical and morphological properties of CTS thin films were studied. Films have tetragonal structure. It was observed that films prepared using stannic chloride had optimum band gap for solar cell application. Hall measurement results proved that all samples were p-type having electrical resistivity of ∼10−3 ohm cm. Using these films, Cu2SnS3 (CTS)/In2S3 (InS) solar cells were prepared (with structure ITO/CTS/InS/Ag). Solar cell fabricated with stannic chloride precursor shows four times enhancement in cell efficiency.