Abstract
The exploration of advanced materials through rational structure/phase design is the key to develop high-performance lithium-ion capacitors(LICs).However,high complexity of material preparation and diffi-culty in quantity production largely hinder the further development.Herein,Cu5FeS4-x/C(CFS@C)hetero-junction with rich sulfur vacancies has successfully achieved from natural bornite,presenting low cost-effective and bulk-production prospect.Density functional theory(DFT)calculations indicate that rich vacancies in bulk phase can decrease band gap of bornite and thus improve its intrinsic electron conduc-tivity,as well as the heterojunction spontaneously evokes a built-in electric field between its interfacial region,largely reducing the migration barrier from 1.27 eV to 0.75 eV.Benefited from these merits,the CFS@C electrodes deliver outperformed lithium storage performance,e.g.,high reversible capacity(822.4 mAh/g at 0.1 A/g),excellent cycling stability(up to 820 cycles at 2 A/g and 540 cycles at 5 A/g with re-spective capacity retention of over or nearly 100％).With CFS@C as anode and porous carbon nanosheets(PCS)as cathode,the assembled CFS@C//PCS LIC full cells exhibit high energy/power density characteris-tics of 139.2 Wh/kg at 2500 W/kg.This work is expected to offer significant insights into structure modi-fications/devising toward natural minerals for advanced energy-storage systems.
基金项目
National Natural Science Foundation of China(52004338)
National Natural Science Foundation of China(22378431)
Hunan Provincial Natural Science Foundation(2022JJ20075)
Hunan Provincial Natural Science Foundation(2023JJ40210)
Scientific Research Fund of Hunan Provincial Education Department(21B0017)
Central South University Innovation-Driven Research Programme(2023CXQD008)
NETL
NSTL
万方数据