Wood-derived carbon electrode for all-solid-state supercapacitor with ultrahigh volumetric and area capacitances

With the development of emerging electronic devices, there is a growing requirement for advanced energy storage systems. Herein, a cost-effective, facile, and sustainable process is developed through to produce an all-solid-state supercapacitor (ASC) from lignocellulosic biomass with wood-derived carbon electrode. The micro/nanostructures of the carbon electrode can be facile altered via biomass pretreatment and hot-pressing process. Ultrahigh volumetric and areal capacitances of 31.4 F cm −3 (5 mA cm −3 ) and 12.5 F cm −2 (5 mA cm −2 ) were achieved, respectively. It also exhibits an outstanding capacitance of 19.7 F cm −3 (20 mA cm −3 ) and 8.6 F cm −2 (20 mA cm −2 ). Significantly, the ASC assembled from the carbon electrode has high capacitance of 16.2 F cm −3 and high energy density of 1.82 mWh cm −3 , and maintains a capacitance retention of over 90 % after 5000 charging/discharging cycles. These performances allow to open up new opportunities to produce sustainable wood-derived electrodes for the applications in energy storage. • Hot-pressing can notably alter the structure of wood-derived carbon electrode. • The carbon electrode shows both ultrahigh volumetric and areal capacitances. • The supercapacitor exhibits an outstanding supercapacitance.