Chemical Stability Of The Cu2sns3/Mo Interface

Cu2SnS3 is an earth abundant semiconductor researched for photovoltaic applications. Due to the small energy difference in the Sn2+/(4+) oxidation states and low free energy of MoS2, the Cu2SnS3/Mo interface is unstable and Cu2SnS3 decomposes. The interface is stabilized by growing Cu2SnS3 on a thin MoS2 layer. Photoluminescence occurs only at the back of the Cu2SnS3 layers when grown on MoS2 and no quantifiable amounts of Cu and Sn are measured at the MoS2 substrate. The quenching of emission of Cu2SnS3 grown on Mo is due to binary sulfides formed in presence of Mo which are not formed when Cu2SnS3 is grown on MoS2.