Free-standingβ-Ta_(2)O_(5)/SWCNTs composite film for high-rate Li-ion storage  

作　　者：WU ZhiMin LIU JiaJia HE XingYu BIAN Jing ZHU XianJun CHEN JianMei LI JianMin 

机构地区：[1]College of Electronic and Optical Engineering&College of Flexible Electronics(Future Technology),Nanjing Universityof Posts and Telecommunications,Nanjing 210023,China [2]Department of Pathology College of Medicine,University of Cincinnati,Cincinnati,OH 45267,USA

出　　处：《Science China(Technological Sciences)》2024年第2期616-626,共11页中国科学（技术科学英文版）

基　　金：financial support from the National Natural Science Foundation of China(Grant No.22105106);the Natural Science Foundation of Jiangsu Province of China(Grant No.BK20210603);Nanjing Science and Technology Innovation Project for Overseas Students(Grant No.NJKCZYZZ2022-05);Start-up Funding from NUPTSF(Grant No.NY221003)。

摘　　要：The rapid development of portable and wearable electronic devices is responding to the urgent demand for high-efficiency flexible energy storage devices.Flexible supercapacitors,showing long cycle life,high power density,and good safety,are considered ideal candidates.Nevertheless,the relatively low energy density restricts their practical applications.With a large dielectric constant of 18-46,Ta_(2)O_(5)-based materials typically exhibit excellent electron-binding ability,which is critical for enhancing the energy density of supercapacitors.In this work,the free-standingβ-Ta_(2)O_(5)/single-walled carbon nanotubes(SWCNTs)composite film was prepared,with a highβ-Ta_(2)O_(5)loading of over 70%.By anchoringβ-Ta_(2)O_(5)nanoparticles onto the surface of SWCNTs,the system’s flexibility and conductivity were significantly enhanced,which also facilitated the intercalation electrodynamics of metal cations.As a result,the flexibleβ-Ta_(2)O_(5)/SWCNTs film exhibits excellent Li-ion storage performance,with a high volumetric specific capacitance of 392.3 F cm^(-3)at the scan rate of 10 mV s^(-1)and 198.9 F cm^(-3)at 500 mV s^(-1).In addition,the asymmetric device,assembled by theβ-Ta_(2)O_(5)/SWCNTs and activated carbon films,shows a high energy density of 45.5 Wh kg^(-1)at the power density of 10.8 kW kg^(-1).This technique opens up a new avenue for improving the energy density and rate performance of flexible supercapacitors.

关 键 词：PSEUDOCAPACITOR Li-ion storage β-Ta_(2)O_(5)/SWCNTs film flexible device high-rate capability 

分 类 号：TB383.2[一般工业技术—材料科学与工程] TM53[电气工程—电器]