1.82 wt.% Pt/N, P co-doped carbon overwhelms 20 wt.% Pt/C as a high-efficiency electrocatalyst for hydrogen evolution reaction

Abstract

Cost-effective electrocatalysts for the hydrogen evolution reaction (HER) play a key role in the field of renewable energy. Although tremendous efforts have been devoted to the search of alternative materials, Pt/C is still the most efficient electrocatalyst for the HER. Nevertheless, decreasing the loading of Pt in the designed eletrocatalysts is of significance. However, with low Pt loading, it is challenging to maintain excellent catalytic performance. Herein, a new catalyst (Pt/NPC) was prepared by dispersing Pt nanoparticles (PtNPs) with an average diameter of 1.8 nm over a three-dimensional (3D) carbon network co-doped with N and P. Because of the high electronegativity of the N and P dopants, PtNPs were uniformly dispersed on the carbon network via high electronic affinity between Pt and carbon, affording a Pt/NPC catalyst; Pt/NPC exhibited superior HER activity, attributed to the down-shift of the Pt d-band caused by the donation of charge from N and P to Pt. The results show that Pt/NPC with an ultralow Pt loading of 1.82 wt.% exhibits excellent HER performance, which corresponds to a HER mass activity 20.6-fold greater than that observed for commercial 20% Pt/C at an overpotential of 20 mV vs. RHE.