PtCu nanoalloy loaded on sulfur-doped porous g-C3N4 for electrocatalytic hydrogen evolution

Abstract

Graphitic carbon nitride (g-C₃N₄), as a carbon support material with excellent stability and abundant active sites, has found widespread applications in various fields, including photocatalytic water splitting, electrolysis of water, and CO₂ reduction. Presently, research on the modification of g-C₃N₄ primarily focuses on atomic doping, defect engineering, and the decoration of metal nanoparticles. In this study, a method involving the high-temperature pyrolysis of a solution containing thiourea and urea was successfully employed to synthesize sulfur-doped porous g-C₃N₄ (S-C₃N₄) nanosheets. Subsequently, PtCu nanoparticles were loaded onto the S-C₃N₄ through a hydrothermal process. In the case of Pt loading of less than half of 20% Pt/C, this catalyst exhibited a low overpotential of only 10 mV at a current density of 10 mA cm⁻², which is significantly better than the 35 mV overpotential of 20% Pt/C. Furthermore, after a long period of continuous current stability testing, the overpotential of the catalyst did not increase by more than 30 mV, demonstrating excellent stability. The porous S-C₃N₄ nanosheets possess a large specific surface area, providing abundant active sites for the HER reaction. This research introduces a fresh method for creating innovative catalysts based on Pt alloys supported by a carbon carrier.