  For electrochemical hydrogen evolution reaction (HER), developing
high-performance catalysts without containing precious metals has been a major
research focus in the current. Herein, we show the feasibility of HER catalytic
enhancement in Ni-based materials based on topological engineering from hybrid
Weyl states. Via a high-throughput computational screening from 140 000
materials, we identify a chiral compound NiSi is a hybrid Weyl semimetal (WSM)
with showing bulk type-I and type-II Weyl nodes and long surface Fermi arcs
near the Fermi level. Sufficient evidences verify that topological charge
carriers participate in the HER process, and make the certain surface of NiSi
highly active with the Gibbs free energy nearly zero (0.07 eV), which is even
lower than Pt and locates on the top of the volcano plots. This work opens up a
new routine to develop no-precious-metal-containing HER catalysts via
topological engineering, rather than traditional defect engineering, doping
engineering, or strain engineering.
