Monodispersed ruthenium nanoparticles interfacially bonded with defective nitrogen-and-phosphorus-doped carbon nanosheets enable pH-universal hydrogen evolution reaction

Herein, we significantly accelerated the kinetics of hydrogen evolution reaction (HER) by interfacially bonding ruthenium nanoparticles with defect-rich nitrogen and phosphorus co-doped carbon nanosheets (Ru/d-NPC). The optimal Ru/d-NPC therefore achieves ultralow overpotentials of 23, 61, and 68 mV at the current density of 10 mA cm−2 for HER in alkaline, neutral, and acidic electrolytes, respectively, demonstrating the excellent pH-universal HER activities. Specially, our Ru/d-NPC catalysts represent a 2 × advance in mass activity (639.9 mA/mgRu) compared to benchmarking Pt/C catalysts (320 mA/mgPt) and high per-site activity (0.13 s−1) under alkaline conditions while remaining the excellent stability under all pH conditions. We experimentally demonstrated that Ru-N bonds at the interfaces of Ru/d-NPC strengthen the metal-support interaction and modulates the electronic structure of Ru, optimizing the intrinsic HER kinetics and sintering-resistance of active Ru species, as further rationalized by theoretical calculations. This work shines the light on the effect of interfacial bonds on the intrinsic HER kinetics.