Ru branched nanostructure on porous carbon nanosheet for superior hydrogen evolution over a wide pH range

Water-electrolytic hydrogen production has attracted extensive attention due to it can fully utilize renewable energy sources and residual secondary energy, while the sluggish kinetics reaction rate seriously hinders the hydrogen evolution reaction (HER) progress. Herein, we reported a novel and simple precipitation-calcination method for the synthesis of Ru branched nanostructures on porous N-doping carbon nanosheets (Ru BCNNs/PNC NNSs) with rough surface and step and edge atoms. The overpotentials for Ru BCNNs/PNC NNSs are 33.4 mV, 81.3 mV, and 99.9 mV in acidic, alkaline, and neutral media, respectively, to achieve the current density of 10 mA cm −2 , indicating the superior HER performance over a wide pH range due to the unique rough surfaces and abundant of steps and edges atoms. Meanwhile, the Tafel slopes are 21.7 mV dec −1 , 111.1 mV dec −1 , and 104.7 mV dec −1 for Ru BCNNs/PNC NNSs in 1.0 M HClO 4 , 1.0 M KOH, and 1.0 M phosphate buffer solution (PBS, pH=7.0), respectively, much lower than that of commercial Pt/C catalysts with mass loading of 10 % from Macklin Inc. (Pt/C-MK). Furthermore, due to the advantages of the strong interface binding energy between Ru and N-C, the Ru BCNNs/PNC NNSs show outstanding durability for HER not only in mild conditions but also in harsh conditions, outperforming most Ru-based electrocatalysts reported previously.