Hydrous RuO2 nanoparticles have been uniformly deposited onto nitrogen-enriched mesoporous carbons (NMCs) via a facile hydrothermal method. The nitrogen doping in the carbon framework not only provides reversible pseudocapacitance but also guides uniform deposition of RuO2 nanoparticles. As a result, an extremely high specific capacitance of 1733 F/g per RuO2, comparable to the theoretic capacitance of RuO2, is reached when 4.3 wt % of RuO2·1.25H2O is loaded onto the NMCs. Systematic studies show that either nitrogen-free or excess nitrogen doping result in RuO2 clusters formation and worsen the electrochemical performances. With intermediate nitrogen and RuO2 content (8.1 wt % N, 29.6 wt % of RuO2·1.25H2O), the composites deliver excellent power performance and high specific capacitance (402 F/g) with reversible capacitive response at 500 mV/s. The unique properties of nitrogen in textual, morphological, and electrochemical aspects may also provide further understanding about the effects of nitrogen doping and metal oxide deposition on supercapacitor performance.
All Science Journal Classification (ASJC) codes
- Materials Science(all)
- high power performance
- hydrothermal method
- nitrogen-enriched mesoporous carbon
- ruthenium oxide