First row transition metal doped B12P12 and Al12P12 nanocages as excellent single atom catalysts for the hydrogen evolution reaction

The hydrogen evolution reaction (HER) is a promising process to produce high purity hydrogen gas. However, the overpotential of this reaction hinders its practical applications. Single atom catalysts (SACs) are recently investigated by the scientific community to facilitate the HER. Herein, we studied the doping of late first-row transition metals on the B12P12 and Al12P12 nano-cages as SACs via density functional theory (DFT) calculations. Results show that all transition metals are chemisorbed on the support, with interaction energies ranging from −0.65 to −3.85 eV. The calculated Gibbs free energies of hydrogen evolution are −0.01, −0.06 and −0.20 eV for Ni@Al12P12, Ni@B12P12, and Co@B12P12, respectively, which are close to the optimum value of 0.00 eV, and comparable to the highly active Pt-based catalysts in literature. Our results indicate that the designed Ni@Al12P12, Ni@B12P12, and Co@B12P12 SACs are excellent candidates as noble metal-free, sufficiently stable, and highly efficient electrocatalysts for HER.