Facile preparation of S, O-codoped carbon materials from wasted pulping liquid for supercapacitors

Abstract

Hierarchical porous carbon S, O-doped is prepared by a facile and green way using industrial red pulping liquid as precursor and mild potassium chloride as initial templates to initiate templates regeneration. Replacement reactions occurs between potassium chloride and sodium atoms on precursors to form a more stable sodium chloride template, which is used to adjust pore structure during the etching process. Rich phenolic structures and sulfur groups in precursor result in the prepared porous carbon with many advantages for supercapacitors, including excellent specific surface area (1873.6 m2 g−1), high graphitization degree, hierarchical porosity and rich heteroatom content. The specific capacitance of fabricated samples can successfully achieve 386.9 F g−1. In addition, assembled energy storage device shows a remarkable energy density 8.6 Wh kg−1 at 21 kW kg−1 power density, and after 10,000 cycles, specific capacitance retention rate can be 86.4%. The superior electrochemical performances demonstrate a great potential candidate of industrial wastes for energy storage devices with excellent properties.