Direct growth of SnS nanowall photoanode for high responsivity self-powered photodetectors.

Tin sulfide (SnS) has attracted growing attention due to its environmental friendliness, tunable band gap and potential applications for high-sensitivity photodetectors. However, the low responsivity and slow response speed severely hinder its further applications. In this work, SnS nanowalls have been successfully fabricated on FTO substrates by a facile hydrothermal approach. The prepared SnS nanowalls were used as a photoanode material for photoelectrochemical (PEC)-type photodetectors. The SnS based PEC-type photodetectors exhibit excellent photocurrent density (39.06 μA cm), responsivity (1460 μA W), long-term cycling stability and self-powered behavior. The responsivity of the detector is higher than that of most reported SnS based PEC-type photodetectors and even some SnS based photoconductive photodetectors. The high responsivity and self-powered behavior enable the extended potential applications of SnS in PEC-type photodetectors.