Unveiling the electrocatalytic potential of main-group metal-doped blue phosphorene for oxygen and hydrogen evolution reactions through a computational study

The large-scale application of water electrolysis requires high-efficiency and low-cost electrocatalysts for the oxygen evolution reaction (OER) and hydrogen evolution reaction (HER). A systematic investigation using first principles calculations has explored the electrocatalytic potential of eleven main-group metal-doped blue phosphorenes (M-BPs) for the OER and HER. Sb-BP and Sn-BP exhibit remarkable OER activity, while Be-BP and Al-BP show promising HER activity. Sb, Be dual-doped BP (SbBe-BP) shows exceptional bifunctional OER/HER performance, with overpotentials of only 0.21/0.02 V, stemming from the synergistic effects of Sb, Be dual-doping and the cooperative interaction between the metal dopants and the substrate. Moreover, graphene functions as a conductive substrate, enhancing the conductivity of Sb-BP, Be-BP, and SbBe-BP via the creation of van der Waals (vdW) heterojunctions, while preserving their catalytic activities, thus paving the way for practical application of main-group metal-doped BP in water electrolysis. Notably, it is found that the adsorption of reaction intermediates can modulate the interlayer coupling strength of vdW heterojunctions, thereby influencing the adsorption free energy of reaction intermediates. This finding offers a distinct perspective to further our comprehension of the catalytic activity of vdW heterojunctions. Sb, Be dual-doped BP shows exceptional bifunctional OER/HER performance.