Rationally designed N/P dual-doped ordered mesoporous carbon for supercapacitors

Heteroatom-doped mesoporous carbons have gained significant attention for their high energy density in supercapacitors. In this present study, we report the synthesis of nitrogen (N) and phosphorous (P) co-doped ordered mesoporous carbon (NPMC) by a simple and scalable technique wet impregnation method in one step using an ordered mesoporous silica template (SBA-15). Low-angle XRD patterns, transmission electron micrographs and N-2 sorption measurement confirmed the synthesized materials ordered mesoporous nature (interconnected honeycomb 2D hexagonal pores of size similar to 10 nm). The charge storage capacity of NPMC is explored both in aqueous and non-aqueous electrolytes. NPMC exhibited a significant faradaic process in an aqueous medium, whereas it was absent in non-aqueous. NPMC delivered a high specific capacitance of 183 F g(-1) with remarkable capacitance retention of 94% even after 10000 charge-discharge cycles at 5 A g(-1) current density in the aqueous medium. In a nonaqueous medium, NPMC exhibited an impressive energy density and power density of 41 Wh kg(-1) (@1 A g(-1)) and 14400 W kg(-1) (@20 A g(-1)), respectively. The retention of the ordered mesoporous structure of carbon with doping is the novelty of this work. It paves new ways to generate high-performance materials compared to the undoped ones for supercapacitor and battery applications. [GRAPHICS] .