Graphitized Loofah Sponge-Derived Carbon for Supercapacitors with Superior Volumetric Capacitance

Biomass-derived carbons (BDCs) have achieved huge improvements in pore structures and performance when prepared by chemical activation, resulting in single pore distribution and deteriorating electrical conductivity yet. It is the greatest challenge to obtain high graphitization BDCs with attractive electrochemical performance at high mass loading of active materials. Partially graphitized loofah sponge-derived carbon (CLC) is successfully prepared by metal ion-assisted activation and high-temperature annealing, exhibiting a high specific surface area of 1133.8 m(2) g(-1) and rich nitrogen and oxygen content. Attributing to the structural advantages and the retained macropore network, the CLC loaded with 10 mg cm(-2) demonstrated a volumetric capacitance (C-V) of 1 188.8 F cm(-3) at a current density of 0.2 A g(-1) and an impressive capacitance retention of 97.7% after 15,000 charge/discharge cycles. This work proposes an economical and feasible synthetic route for the preparation of highly graphitized BDCs, offering the possibility of large-scale synthesis of ideal performance supercapacitor (SCs) electrode materials.