Chemistry of Tin Monosulfide (δ-SnS) Electrodeposition

The conditions of formation of a tin sulfide phase by galvanostatic deposition with tartaric acid were investigated, changing parameters such as pH (1.5 and 2.5) and temperature (50, 70, and ). Uniform films were deposited at both pH's. Cyclic voltammetry data suggested that tin-tartrate complexes were crucial to film electrodeposition and also indicated reduction of sulfur species rather than tin. X-ray diffraction showed the structure to be a pure phase over the range of deposition temperatures at pH 2.5. This observation was limited to for films deposited at pH 1.5. Impurities of Sn and were found in films deposited at pH 1.5 and temperatures of 50 and , respectively, indicating that the phase is more likely to be formed at lower pH's. All the films annealed at displayed the phase. Scanning electron microscopy showed deposited particles increased in size and became more platelike with increasing temperatures of electrodeposition, but did not change morphology with annealing. spectrometry confirmed increased disorder in films deposited at and a direct allowed optical bandgap of lower energy for the phase compared to that of .