Topological understanding of catalyst
The vital role of electrocatalysts in determining the efficiency of renewable energy conversion inspired the uncover of the relation between catalytic efficiency and electronic structure, in which the volcano-type plot based on the surface properties of adsorption energies and d-band model has achieved great success. To have a deeper understanding of the relation between electrocatalysts and materials electronic structures, we try to extract a pure intrinsic physical parameter, projected Berry phase (PBP), namely γ in our recently work, that only depends on the bulk electronic structure. Applying this parameter to the well-known non-magnetic transition metal electrocatalysts, we found a good linear relationship between PBP and exchange current densities for the hydrogen evolution reaction (HER) after considering the symmetry constraint. This parameter can be understood as a topological effect since it reflects the Berry phase geometry effect. This work illustrates the importance of the pure bulk band structure effect on electrochemical activities and implies an effective way to understand the mechanism of HER catalyst and search for materials with improved catalytic performance. Based on the understanding of the relation between topological band structure and catalysis efficiency, a new record was found in d-band based topological materials.