Wood-based self-supporting flexible electrode materials for energy storage applications

Abstract

Generally, electrochemical energy storage devices share fundamental processes involving the diffusion and storage of ions and transport of electrons in electrode materials. Oriented 3D carbon materials can achieve better rapid ion diffusion and rapid charge conduction at the same time due to their low tortuosity and orderly conduction path. In this work, oriented microchannel carbon materials were prepared by carbonizing delignified poplar wood slices. The delignified wood-based carbon material displays massive intertubular lumina and unique aligned microchannel structure, which imparts good flexibility. This unique structure not only significantly increases the surface area of the electrode material accessible by the solid electrolyte, but also forms efficient and orderly electron conduction paths. In addition, the unique porous aligned microchannel structure also provides huge possibilities for regulating energy storage performance. The PANI nanowire array evenly covered the surface of the aligned carbon microchannel, and the unique porous aligned microchannels could be effectively retained. The DWCPA-1 interdigitated flexible solid supercapacitor exhibits significantly better electrochemical performance, cycle stability and folding endurance than that by the DWFC-800 based flexible interdigital solid supercapacitor. This indicates that the delignified wood-based flexible carbon material is an ideal basic flexible self-supporting electrode material, which has a good application potential in the field of flexible solid-state energy storage.