Fig. 2: Reaction mechanism studies by DFT calculations.
From: Unusual Sabatier principle on high entropy alloy catalysts for hydrogen evolution reactions
a The distribution of ΔGH* on HEA with 5.9% compressive strain (5.9%-HEA), including different adsorption sites (hcp hollow site, fcc hollow site, and bridge site). The red dashed circles indicate the active centers for Volmer and Heyrovsky (or Tafel) steps, respectively. The green area represents the diffusion region (DR) for the adsorbed H*. b Volmer–Heyrovsky mechanism of HER on 5.9%-HEA (111) and Pt (111). c Volmer-Tafel mechanism of HER on 5.9%-HEA (111) and Pt (111). d The H* spillover on DR1 (diffusion region for the first H*) for 5.9%-HEA (111). e The H* spillover on DR2 (diffusion region for the second H*) for 5.9%-HEA (111).
