Rice husk/coal tar pitch based hierarchical porous carbons as the cathode of zinc ion hybrid capacitors
PENG Guodong
ZHU Aoyang
ZHU Yiquan
LI Yong
HE Xiaojun
Abstract：Zinc-ion hybrid capacitors(ZHCs)have attracted increasing attention due to their advantages such as low cost,improved safety and long-term cycling stability.However,despite these advantages,the development of ZHCs is still in its early stages and faces a number of challenges,such as the growth of electrode dendrites and the energy density is still unsatisfactory.Therefore,it is extremely crucial to develop reasonably matched electrode materials.Porous carbon materials have become one of the most potential cathode materials for ZHCs because of the advantages of low price,high porosity and stable performance.However,the low conductivity and inappropriate pore size distribution of traditional porous carbon materials limit their application in ZHCs.It is hoped that the problems can be tackled through the selection of raw materials and structure design.Herein,the hierarchical porous carbons(HPC/RHCx)were prepared from rice husk and coal tar pitch using double template of KCl and MgO coupled with K2CO3 activation strategy.The HPC/RHC6 features interconnected nanocapsule-like structure,large specific surface area(1 234 m2/g)and hierarchical pore structure.As the cathode material of ZHCs,HPC/RHC6 exhibits excellent zinc storage performance.At the current density of 0.1 A/g,the specific capacity of HPC/RHC6 reaches 125.3 mA·h/g,and at the power density of 115.4 W/kg,the energy density is 92.4 W·h/kg.After 10 000 cycles of charge and discharge at a current density of 5 A/g,the capacity retention is 99.9％,showing excellent cycle stability.
Keywords：zinc-ion hybrid capacitorscathode materialscoal tar pitchporous carbonzinc-storage performance
Publication Date：2025-01-31
Online Publishing Date：2025-08-15(First online date of this platform, not the publication date of the document)
Pages：9( 86-94 )