High-performance microporous carbon from deciduous wood-origin metal carbide

Abstract

Abstract A biomorphic microporous carbon is of a great interest in many applications, including energy storage, due to the cheap and “green” precursor materials. The macroscopic texture of carbon, which copies that of biologic precursor, benefits an access to the micropores. In this study, the novel wood-origin carbide-derived carbon (wCDC) was prepared by chlorinating of biomorphic TiC, made by carbothermal reduction of a mixture of metal oxides and incompletely pyrolyzed deciduous wood-origin charcoal. The X-ray diffraction analysis confirms complete conversion of carbide into amorphous carbon, whereby scanning electron microscopy shows the precursor-like morphology of wCDC comprising plurality of small sub-micrometer sized particles assembled in highly porous carbon matrix. The N2 and CO2 adsorption studies reveal the enhanced microporous structure of wCDC compared to common TiC derived carbon. Surface chemistry of novel carbon material was explored by infrared and X-ray photoelectron spectroscopy. The energy dispersive and X-ray fluorescence spectroscopy studies reveal that most of the wood-origin inorganic impurities in as-synthesized wCDC can be removed in aqueous media. This study shows that carbothermal reduction is a facile method for producing biomorphic precursor for microporous carbon material with very high accessible surface area and superior energy storage capability in nonaqueous electrolyte. Electrochemical evaluation of the wCDC with specific surface area of ∼2500 m2 g−1 yielded specific capacitance of ∼190 F g−1 in EMIm-BF4 based electrolyte, which is considerably more than that of the common TiC-derived microporous carbon in the same electrolyte.