Metallic transition metal dichalcogenides, such as tantalum disulfide (TaS2), have recently emerged as promising electrocatalysts for the hydrogen evolution reaction. This work reports an effective strategy to further tune their performance through interfacial engineering, including lattice mismatch and electron injection between electrocatalysts and the underlying substrates. A unique two-zone chemical vapor deposition technique has been developed, and 2D TaS2 has been successfully grown on four different substrates, including glassy carbon, carbon fibers, Mo foil, and Au foil, providing excellent platforms to study catalyst-substrate interactions. Among them, TaS2 on Au foil offers the best performance with lowest overpotential and smallest charge transfer resistance, due to a suitable lattice mismatch and charge injection between TaS2 and Au, as revealed by theoretical calculations and experimental measurements. This work highlights the key roles the substrate plays in the catalysis and demonstrates the validity of interfacial engineering in catalyst design.
Keywords: density functional theory; electron injection; hydrogen evolution; lattice mismatch; tantalum disulfide; two-dimensional materials.