Nitrogen-Doped Reduced Graphene Oxide Hydrogel Achieved via a One-Step Hydrothermal Process

We report a one-step method to efficiently achieve reduced graphene oxide hydrogel doped with nitrogen using ammonium formate as reducing reagent and nitrogen supplier by means of hydrothermal method. The resultant materials exhibit C/O atomic ratio as high as similar to 10.9 and contains decent nitrogen doping (similar to 5.2 at. %). As a comparison, only solid precipitates of lower reduction efficiency and no nitrogen doping are obtained when L-ascorbic acid is used. Electrochemical measurements show that the nitrogen-doped reduced graphene oxide exhibits enhanced electrocatalytic ability for oxygen reduced reaction, indicating its great potential as low-cost and precious-metal-free catalyst for energy storage applications.