Controlled Synthesis of a Hierarchically Porous N‐Doped Carbon Material with Dominantly Pyrrolic Nitrogen Using a Self‐Sacrificial SBA‐15 Template for Increased Supercapacitance

Abstract

AbstractHerein, we report an effective strategy to synthesise a hierarchically porous pyrrolic nitrogen‐dominated doped carbon material (N‐doped carbon material) by the low‐temperature carbonisation and post‐KOH activation of a 3‐fluorophenol‐3‐aminophenol‐formaldehyde co‐condensed resin using a self‐sacrificial SBA‐15 template. Low‐temperature thermal treatment successfully prevented the transformation of the thermally unstable and pseudocapacitance‐active pyrrolic nitrogen to pseudocapacitance‐inactive graphitic nitrogen configurations. Additionally, the combined effect of the self‐sacrificial SBA‐15 template and KOH activation resulted in a high specific surface area of 582 m2 g−1 and hierarchical microporous/mesoporous architecture, thereby maximising the exposure of electrochemically active sites. The N‐doped carbon material exhibited an outstanding specific capacitance of 532.8 F g−1 (electrochemical double‐layer capacitance of 331.2 F g−1 and faradaic pseudocapacitance of 201.6 F g−1) at a scan rate of 1 mV s−1 and stability with the retention of nearly 100 % at a current density of 10 A g−1 after 10000 cycles.