Robust ruthenium diphosphide nanoparticles for pH-universal hydrogen evolution reaction with platinum-like activity

Abstract Development of cost-effective and durable electrocatalysts with Pt-like activity for pH-universal hydrogen evolution reaction (HER) is highly desirable but challenging. Herein, we report a new methodology for facile fabrication of robust electrocatalysts consisting of N, P-codoped carbon (NPC)-encapsulated RuP2 nanoparticles around carbon nanotubes (CNTs), which shows unprecedented HER activity and high durability in all-pH range. The method involves the conformal coating of the imidazolium-based ionic polymer (ImIP) on CNTs surface, anion metathesis and subsequent phosphorization, the multistep synthetic protocol allows for deliberate modulation of the electrocatalysts. ImIP effectively inhibits the aggregation of RuP2 during phosphorization to form small-sized RuP2 nanoparticles, while NPC significantly increases the conductivity, intrinsic activity and stability of RuP2. The remarkably low overpotentials of 12, 15 and 13 mV are required to achieve a current density of 10 mA cm−2 in 1.0 M KOH, 1.0 M PBS and 0.5 M H2SO4, respectively. This work provides a feasible method to develop new type of Pt-like electrocatalysts for HER in all-pH range.