Molten salt derived Mo2AlB2 with excellent HER catalytic performance

Abstract

Mo2AlB2 is a lamellar transition metal boride that is prepared by selectively etching the MoAlB MAB phase precursor. Most methods for synthesizing Mo2AlB2 require the use of strong acids or bases and a long reaction time. In this study, we present a Lewis acid molten salt method for synthesizing the lamellar structured Mo2AlB2 by selectively etching a layer of aluminium atoms from the MoAlB precursor. The synthesized Mo2AlB2 shows excellent catalytic activity for hydrogen evolution reaction under alkaline conditions, with long-term stability, and a low overpotential of 145 mV and Tafel slope of 76 mV dec−1 at 10 mA cm−2.