One Stone, Three Birds: A self-templating/activating route to synthesize nitrogen-doped porous carbon nanosheets for high-performance supercapacitors

The porous texture and surface chemistry of carbon materials impose remarkable influence on their use in supercapacitors. Herein, we demonstrate a straightforward self-templating/activating method to synthesize carbon nanosheets with high porosity and rich nitrogen incorporation. The crosslinking network between organic salts (i.e., potassium citric) and urea plays triple-roles of in situ templating, activating, and doping upon condensation pyrolysis, which favorably guide the one-step formation of nitrogen-enriched porous carbon nanosheets. Benefiting from the high surface area and nitrogen doping, the as-received carbon materials manifest superior supercapacitive properties, including a high specific capacitance of 373 F/g, excellent rate performance, and a prominent 97.5 % retention over 10,000 cycles. The present work can provide a simple yet powerful tactic to advance the development of nitrogen-doped and hierarchically porous carbon for high-performance supercapacitors.