P- or S-Doped Graphdiyne as a Superior Metal-Free Electrocatalyst for Hydrogen Evolution Reaction: A Computational Study

Searching for stable, efficient, and inexpensive metal-free electrocatalysts for the hydrogen evolution reaction (HER) is crucial for sustainable hydrogen generation. Herein, by means of density functional theory (DFT) computations, we proposed that P- or S-doping can effectively activate the basal plane of graphdiyne (GDY) for the HER. Our results revealed that these P- or S-doped GDY materials exhibit outstanding stability, enhanced electrical conductivity, and excellent magnetic properties. More interestingly, by carefully controlling the site and type of the P or S heteroatom, GDY can exhibit superior catalytic performance for the HER with the hydrogen adsorption free energy (ΔGH*) being near zero, which can be attributed to its moderate p-band centers near the Fermi level. Our work highlights a novel metal-free electrocatalyst for the HER, providing a promising strategy to rationally design highly efficient HER catalysts for sustainable H2 production.