Screening Out the Transition Metal Single-Atom Supported on Onion-Like Carbon (Olc) for the Hydrogen Evolution Reaction

A recent experiment has confirmed that onion-like nanospheres of carbon (OLC) covered with single Pt atoms show comparable hydrogen evolution reaction (HER) catalytic activity to the commercial Pt/C. In this work, we have performed screening calculations on the single transition metal (TM) atom supported on OLC (a total of 26 candidates) using the density functional theory (DFT) to find excellent HER catalysts. Our calculated results indicate that the Nb/CLO, Mo/CLO, Ru/CLO, Rh/CLO, Pd/CLO, and Ir/OLC show high-efficient catalysts performance for the HER, as experimental Pt/OLC does. We also try to seek an appropriate descriptor relevant to the Gibbs free energies, and the average local ionization energy (ALIE), which is first used to predict HER activity, shows a perfect linear correlation with Gibbs free energy. It is interesting to note that the ALIE descriptor is more successful than the commonly used d-band center.