Temperature controlled phase selective facile synthesis of tin sulfides and their electrochemical HER activity

Abstract

Tin sulfide based semiconductors act as a promising candidate in photo/electro catalysis and solar cell applications owing to its suitable band gap and environment friendly nature. In this article we demonstrate a one-step synthesis of tin sulfides (SnS, SnS2, Sn2S3) via facile gas–solid reaction method. XRD, SEM and XPS analysis were carried out to characterize the samples for phase formation, morphology and valence states of the elements respectively. Bulk layered SnS and Sn2S3 micro-rods were obtained at the operating temperature of 700 °C and 600 °C respectively. Hexagonal nanoplate SnS2 was also obtained as a minor product during the synthesis of SnS. Furthermore, the electrocatalytic HER activity of the ballmilled SnS and Sn2S3 samples showed a considerable reduction in the overpotential of 171 mV and 126 mV respectively. The enhanced HER activity is attributed to the exposed catalytic active sites of the ballmilled samples.