Corresponding Author

Xiao-jun HE(agdxjhe@126.com)


It is still a challenge to prepare carbon materials with high specific surface area at low cost from renewable resources. Herein, the authors report an efficient approach to synthesize porous carbons (PCs) from rice husk with ionic liquid (1-butyl-3-methylimidazolium hexafluorophosphate (BMIMPF6)) as a template and an activation agent. The as-made PCs featured the high specific surface area up to 1438 m2·g-1. As electrodes for supercapacitors, PCs showed a high specific capacitance of 256 F·g-1 at 0.05 A·g-1 in 6 mol·L-1 KOH aqueous electrolyte and a good rate performance of 211 F·g-1 at 10 A·g-1. All the PC electrodes exhibited good cycle stability. This work provides a new way for efficient synthesis of PCs from biomass using BMIMPF6 as a template and an assisted activation agent for high-performance supercapacitors.

Graphical Abstract


porous carbon, BMIMPF6, rice husk, supercapacitor

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