3D wood-derived vertical multichannel carbon framework with functional fillers for high-performance Zn-ion hybrid supercapacitors

Abstract

Severe dendrite and side reaction issues of metallic zinc anodes are vital factors that result in the poor cycling ability of aqueous zinc-ion hybrid supercapacitors (ZHSCs). Herein, we developed a three-dimensional wood-derived vertical multichannel framework modified by functional fillers. The modified 3D carbon-based framework possesses optimized zincophilicity and a hierarchical porous structure, which can effectively accommodate volume expansion and homogenize local current density for uniform Zn deposition. Thus, the designed 3D carbon-based framework delivers a superior coulombic efficiency of 98.6% over 1300 cycles at 10 mA cm⁻², while the symmetric cell with the carbon-based Zn anode exhibits 1100 h cycles at 1 mA cm⁻² (1 mAh cm⁻²). Moreover, benefiting from its high porosity, the 3D carbon-based framework can be used as a binder-free cathode material for constructing high-performance ZHSCs. The as-designed full cell exhibited a remarkable areal capacitance of 3172.8 mF cm⁻² and extremely long-term cycle stability of 15 000 cycles at 40 mA cm⁻². This strategy of zincophilicity regulation by introducing functional fillers into a 3D carbon-based framework may provide a new idea for fabricating ZHSCs with high stability and capacity.