Two-Dimensional Tantalum Carbo-Selenide for Hydrogen Evolution.

Herein, we report the synthesis of two-dimensional TaSeC (2D-TaSeC) nanosheets using electrochemical lithiation in multilayer TaSeC followed by sonication in deionized water. Multilayer TaSeC was obtained via solid-state synthesis of FeTaSeC followed by chemical etching of Fe. 2D-TaSeC exhibited promising electrocatalytic activity for the hydrogen evolution reaction from water compared to multilayer TaSeC and 2D-TaSe. 2D-TaSeC showed an overpotential at 10 mA·cm (η) of 264 mV, a Tafel slope of 91 mV·dec, and an electrochemically active surface area of 17.61 m·g. The high performance could be attributed to the large surface area of single sheets which hence maximizes the number of exposed catalytic sites and increased density of vacancies, observed with transmission electron microscopy, during synthesis and processing.