Tunable Transformation Between SnS and SnO_x Nanostructures via Facile Anodization and Their Photoelectrochemical and Photocatalytic Performance

Anodic fabrication of tin sulfide is for the first time reported. Through a facile anodization method in a glycerol electrolyte of sodium sulfide, a range of interesting tin sulfide nanostructures are produced in a controllable manner. By changing the anodization parameters (anodization potential, water content, and electrolyte concentration), anodic nanomaterials ranging from pure SnS to SnO_x can be conveniently synthesized. The fabricated SnS/SnO_x multi-heterojunction nanocomposites delivered greatly improved photoelectrochemical and photocatalytic performances, due to the presence of narrow-bandgap SnS (≈1.56 eV) in wide-bandgap SnO_x (≈3.6 eV), which can effectively separate the photoinduced electron-hole pairs and prolong their lifetime. The novel method reported here presents an efficient strategy to directly construct metal sulfides or sulfide/oxide heterojunctions that are directly applicable as electrode materials in photoelectrochemical cells, photovoltaic devices, sensors, and binder-free batteries or supercapacitors.