Correlation between Heteroatom Coordination and Hydrogen Evolution for Single‐site Pt on Carbon‐based Nanocages

The electrocatalytic performance of single‐site catalysts (SSCs) is closely correlated with the electronic structure of metal atoms. Herein we construct a series of Pt SSCs on heteroatom‐doped hierarchical carbon nanocages, which exhibit increasing hydrogen evolution reaction (HER) activities along S‐doped, P‐doped, undoped and N‐doped supports. Theoretical simulation indicates a multi‐H‐atom adsorption process on Pt SSCs due to the low coordination, and a reasonable descriptor is figured out to evaluate the HER activities. Relative to C‐coordinated Pt, N‐coordinated Pt has higher reactivity due to the electron transfer of N‐to‐Pt, which enriches the density of states of Pt 5d orbital near the Fermi level and facilitates the capturing of protons, just the opposite to the situations for P‐ and S‐coordinated ones. The stable N‐coordinated Pt originates from the kinetic stability throughout the multi‐H‐atom adsorption process. This finding provides a significant guidance for rational design of advanced Pt SSCs on carbon‐based supports. A series of Pt single‐site catalysts was constructed and exhibited increasing hydrogen evolution reaction (HER) activities along the S‐, P‐, C‐ and N‐coordinated Pt. The structure‐performance correlation is established. The multi‐H‐atom adsorption deepens the understanding of activity and stability. The density of states (DOS) of Pt 5d orbitals near Fermi level (Ef) can promote the activity by facilitating electron transfer and proton capture.