Unveiling Mesoporous Graphitic Carbon Nitride as a High Performance Electrode Material for Supercapacitors

Abstract

Synthesis of mesoporous graphitic carbon nitride (MGCN) by soft template method is still challenging and its application as an electrode material for supercapacitor remains unexplored. Herein, we introduce MGCN as an electrode material for supercapacitors. MGCN is synthesized by facile direct carbonization of methylolated surfactant-polymer composite and bulk graphitic carbon nitride (BGCN) is synthesized under similar condition but in the absence of surfactant. MGCN displays excellent capacitance properties in 1 M H2SO4 electrolyte with a specific capacitance as high as 279 F g−1 at a current density of 0.25 A g−1. It also exhibits good rate capability and outstanding cycling stability with excellent coulombic efficiency of 100% over 5000 cycles. This superior capacitive storage performance is attributed to the high surface area, easily accessible mesopores and high pyridinic nitrogen content. High surface area and uniform pores of MGCN provide more active sites for charge storage and reduce diffusion path length for ions while high pyridinic nitrogen enhanced the overall specific capacitance by surface Faradaic reaction.