A new compound Pt3Bi2S2 with superior performance for the hydrogen evolution reaction

Abstract

The exploration of efficient electrocatalysts for the hydrogen evolution reaction (HER) is beneficial to obtain renewable clean energy. Herein, a new parkerite-type compound Pt₃Bi₂S₂ was synthesized, constructed by [PtBi₄S₂] octahedra. The Bi 6p orbital electrons upshift the Pt 5d band to promote hydrogen adsorption. Moreover, the Bi–Pt orbital hybridization greatly improves the conductivity and accelerates the charge transfer during the electrocatalytic process. Hence, Pt₃Bi₂S₂ exhibits a superior catalytic activity for the HER with a low overpotential of 61 mV (at j = 10 mA cm⁻²) and a Tafel slope of 51 mV dec⁻¹. In addition, Pt₃Bi₂S₂ has higher stability than commercial Pt/C. This work proposes a promising strategy for designing new excellent HER catalysts.