Pt-Pd co-electrodeposited nitrogenous loofah sponge as efficient pH-universal electrocatalyst for hydrogen evolution reaction

Abstract

Hydrogen, a clean, renewable and efficient energy source, is considered to be one of the most appropriate candidates for traditional fossil fuels. As the most important part of the hydrogen evolution reaction (HER), HER catalysts are receiving ever increasing attention in recent years. In this work, an activated nitrogenous loofah sponge (NLS) with similar nanosheets structure like graphene and MoS2, was introduced as the nanocarbon substrate. Then, Pt, Pd and PtPd nanoparticle modified activated loofah sponge nanocomposites (Pt@NLS, Pd@NLS, PtPd@NLS) were simply obtained via electrochemical deposition in different electrolytes. The HER performances of Pt@NLS, Pd@NLS and PtPd@NLS were fully investigated in both acid and alkaline conditions, which indicated that the PtPd@NLS (electrodeposition for 10 s) with 6.95 wt% Pt and 8.65 wt% Pd had best HER performance in both solutions. The overpotentials of the PtPd@NLS (@ 10 mA cm−2) in 0.5 M H2SO4 and 1.0 M KOH were 29 and 46 mV, respectively. The corresponding Tafel slopes were 23 and 124 mV dec−1, which were quite comparable to the Pt/C (10 wt%). The PtPd@NLS also showed good long-term stability in both media.