Identification of the anti-triangular etched MoS2 with comparative activity with commercial Pt for hydrogen evolution reaction

Abstract

The introduction of anti-triangular dots by etching MoS2 has been recently reported as an efficient way to produce active internal edges. However, it is still ambiguous to identify the configuration of etched MoS2 with comparative hydrogen evolution reaction (HER) activity to commercial Pt. In this work, the HER activity on etched anti-triangular MoS2 are investigated by density functional theory calculations. We found the valence electron distribution of inner edge atoms can be affected by the corner, and accordingly determine their activity. The second-nearest atom to anti-triangular corner possesses the highest activity. The simulated polarization curves show etched anti-triangular Mo-edge MoS2 with moderate size (around 12 Å) maximize the HER performance. Further increasing size of etched MoS2 deactivate their HER activity to a certain degree, validated by available experimental data. This work suggests etched MoS2 catalysts with rational design may be a candidate to substitute Pt electrodes as HER electrocatalyst.