Experimental and theoretical insights to demonstrate the hydrogen evolution activity of layered platinum dichalcogenides electrocatalysts

Hydrogen is a highly efficient and clean renewable energy source and water splitting through electrocatalytic hydrogen evolution is a most promising approach for hydrogen generation. Layered transition metal dichalcogenides-based nano-structures have recently attracted significant interest as robust and durable catalysts for hydrogen evolution. We systematically investigated the platinum (Pt) based dichalcogenides (PtS2, PtSe2 and PtTe2) as highly energetic and robust hydrogen evolution electrocatalysts. PtTe2 catalyst unveiled the rapid hydrogen evolution process with the low overpotentials of 75 and 92 mV (vs. RHE) at a current density of 10 mA cm−2, and the small Tafel slopes of 64 and 59 mV/dec in acidic and alkaline medium, respectively. The fabricated PtTe2 electrocatalyst explored a better catalytic activity than PtS2 and PtSe2. The density functional theory estimations explored that the observed small Gibbs free energy for H-adsorption of PtTe2 was given the prominent role to achieve the superior electrocatalytic and excellent stability activity towards hydrogen evolution due to a smaller bandgap and the metallic nature. We believe that this work will offer a key path to use Pt based dichalcogenides for hydrogen evolution electrocatalysts.