锌基导电有机框架化合物负极用于高比能锂离子电容器的构筑OA

Lithium-ion capacitors(LICs)have emerged as advanced energy storage devices that integrate the high power of supercapacitors and the high energy of lithium-ion batteries,making them highly promising for critical applications such as electric vehicles,portable electronics,and grid-scale energy storage systems.However,the practical deployment and large-scale commercialization of LICs remain hindered by the capacity and kinetic mismatch between the anode and cathode,which leads to poor rate performance and insufficient cycling stability.Therefore,the exploration of novel anode materials with superior kinetic performance and excellent structural stability has become an urgent pursuit for the development of high-performance LICs.Herein,a conductive metal-organic framework(MOF),namely Zn3(HHTP)2(HHTP=2,3,6,7,10,11-hexahydroxytriphenylene),was synthesized via a facile hydrothermal method,and its electrochemical performance as an LIC anode was systematically investigated.The Zn2+ions form coordination bonds with HHTP ligands,constructing a hexagonal lattice that arranges along the c-axis to form a porous honeycomb-like structure.Effective orbital overlap between Zn2+and the ligands endows the material with good electronic conductivity.In addition,the abundant porous architecture facilitates the intercalation and deintercalation of Li+ions,thereby imparting Zn3(HHTP)2 with fast ion diffusion and electron transfer characteristics.Electrochemical tests demonstrated that Zn3(HHTP)2 exhibits excellent rate capability and cycling stability.Specifically,it delivers a specific capacity of 213.7 mAh/g even at a high rate of 5 A/g.Moreover,after 500 cycles at 1 A/g,it retains a capacity of about 325 mAh/g.X-ray photoelectron spectroscopy analysis of the electrode after 50 cycles demonstrated that,in addition to the interlayers and honeycomb pores of Zn3(HHTP)2,organic ligands also serve as important active sites for lithium storage.The LIC device assembled with a Zn3(HHTP)2 anode and an activated carbon(AC)cathode achieves a high energy density of 104.8 Wh/kg at 400 W/kg and still maintains 68 Wh/kg even at a high power density of 2 kW/kg.This work provides new insights and technical support for the broader application of conductive MOFs in electrochemical energy storage.