High-Performance Ru@C₄N Electrocatalyst for Hydrogen Evolution Reaction in Both Acidic and Alkaline Solutions

We report a high-performance Ru@C4N electrocatalyst for the hydrogen evolution reaction (HER) in both acidic and alkaline solutions. This catalyst is synthesized by annealing a complex of a covalent organic framework compound coordinated with ruthenium synthesized by a “one-pot” solvothermal method. This Ru@C4N catalyst shows excellent electrocatalytic activity toward the hydrogen evolution reaction (HER) in both acidic and alkaline solutions with very low overpotentials at 10 mA/cm2 (6 mV in 0.5 M H2SO4 solution; 7 mV in 1.0 M KOH solution), which outperforms the commercial catalyst Pt/C. The Ru@C4N electrocatalyst also exhibits high HER turnover frequencies of 0.93 H2 per s in 0.5 M H2SO4 and 0.65 H2 per s in 1.0 M KOH solutions at 25 mV as well as superior performance stability.