Hybrid Double Atom Catalysts for Hydrogen Evolution Reaction: A Sweet Marriage of Metal and Nonmetal

Abstract

Searching for active and low-cost electrocatalysts for the hydrogen evolution reaction (HER) is crucial to develop sustainable energy, yet it remains a significant challenge. Based on the density functional theory calculations, a new kind of double atom catalysts (HDACs) with hybrid metal and nonmetal center embedded in g-CN is reported for the HER. It is demonstrated that the introduction of the nonmetal atoms (B, C, Si, P, and S) near the metal sites enables unique charge communication between them, which offers diatomic center a very different catalytic activity than the single atom counterparts. Out of 130 HDACs, Pd-B, Ti-C, Ir-C, Cr-Si, Mn-Si, Co-Si, Rh-Si, Au-Si, Ir-P, Fe-S, and Ni-S pairs are identified as the high-performance electrocatalysts with nearly ideal adsorption strength for proton. Machine learning analysis allows to directly identify the key characteristics that affect the catalytic activity and establish a predictable framework for a fast screen of the unknown chemical space of HDACs. This work paves a new avenue for designing and developing potential HER catalysts.