Structural, optical and photoelectrochemical properties of phase pure SnS and SnS2 thin films prepared by vacuum evaporation method

Abstract Two-dimensional (2D) layered semiconducting materials, such as MoS2, SnS2 and SnS, have received remarkable consideration due to their thickness dependent properties and potential applications. In this study, SnS and SnS2 thin films were grown using a simple method of thermal evaporation and their possible application in photoelectrochemical splitting of water reaction have been investigated. X-ray diffraction, Scanning electron microscopy, Raman spectroscopy, and UV–Vis spectroscopy techniques results show the presence of SnS and SnS2 pure phases with orthorhombic and hexagonal crystal structure, having band gap values of 1.8 eV and 2.75 eV, respectively. The photoelectrochemical response of as grown SnS and SnS2 thin films was investigated and the results showed the photoanodic behaviour for SnS2 films with photocurrent density of 1  mA cm−2 and photocathodic nature for SnS with photocurrent density of 0.4 mA cm−2 at 0.95 V vs. Ag/AgCl. The above obtained properties of SnS and SnS2 opens a pathway for using these films for SnS–SnS2 heterojunctions for further improving the photoelectrochemical response.