Highly tunable three-dimensional porous carbon produced from tea seed meal crop by-products for high performance supercapacitors

Abstract

Biomass-derived carbon materials arouse immense research interest in electrochemical energy storage field. Especially, their pore structure has a critical influence on the charge storage performance, so it is always extremely desirable and challenging to achieve the controlled preparation of advanced carbon materials with highly tunable porous structure. In this work, three-dimensional honeycomb-like porous carbon materials are controllably fabricated from the tea seed meal crop by-products. The as-prepared carbon nanostructures showcase the multiple advantages including hierarchical porosity, large surface area, and N, O, S, P self-doping, rendering it promising candidate as electrode material for electrochemical energy storage units. The fabricated carbon electrode indicates a remarkable gravimetric capacitance of 384 F/g at 0.5 A/g in the aqueous electrolyte of KOH, and a suitable steadiness keeping 97.4% of the initial capacitance after ten thousand cycles at 20 A/g. Moreover, using Na2SO4 neutral aqueous electrolyte, the equivalent symmetric supercapacitor device produces a favorable specific energy of 19.17 Wh kg−1 at 500 W kg−1 with a 2.0 V potential window.