Biochar-anchored PtPd bimetallic nanoparticle catalyst for high-efficient hydrogen evolution reaction

Abstract

PtPd bimetallic catalysts have garnered significant attention in the field of hydrogen production via water electrolysis due to their excellent catalytic performance and promising application prospects. There is an urgent need to develop a direct synthesis method for highly efficient and stable PtPd-based nanocatalysts. In this study, a PtPd bimetallic nanoparticle/biochar composite catalyst was synthesized by combining the impregnation method and high-temperature carbonization in situ co-reduction techniques. Leveraging the micro-confinement effect of the biomass cell membrane/wall structure, the PtPd bimetallic nanoparticles were in situ anchored onto the surface of the biomass nitrogen-doped carbon material through the action of ionic chemical bonds. The addition of Pd modulated the electronic structure of Pt, and the synergistic interaction between Pt and Pd, along with the interaction between the PtPd alloy and the C-N support, generated multiple active sites, significantly enhancing the electrocatalytic hydrogen evolution reaction (HER) efficiency. The synthesized PtPd@C-N catalyst exhibited excellent hydrogen evolution activity and long-term stability in 0.5 M H₂SO₄. Among them, Pt₆₅Pd₃₅@C-N achieved a mass activity of 3.56 A/mg at an overpotential of 50 mV, far surpassing that of Pt@C-N, Pd@C-N prepared under the same conditions and is 16 times higher than the mass activity of commercial Pt/C. This study provides a new idea for the preparation of binary alloy nanocatalysts and demonstrates potential application prospects in the fields of energy conversion and storage.