Engineering 3D electron and ion transport channels by constructing sandwiched holey quaternary metal oxide nanosheets for high-performance flexible energy storage  

“三明治”多孔四元金属氧化物纳米片/碳纳米管柔性薄膜电极的构建及其性能研究

作　　者：Pingping Yao Jiali Yu Jie Zhou Shuo Zhang Meng Zhang Huichao Liu Bo Yang Tao Zhang Caizhen Zhu Jian Xu 姚平平;于佳立;周杰;张硕;张盟;刘会超;杨波;张涛;朱才镇;徐坚(Institute of Low-dimensional Materials Genome Initiative,College of Chemistry and Environmental Engineering,Shenzhen University,Shenzhen 518060,China;Research Institute of Tsinghua University in Shenzhen,Shenzhen 518057,China;Institute of Nuclear and New Energy Technology,Tsinghua University,Beijing 100084,China)

机构地区：[1]Institute of Low-dimensional Materials Genome Initiative,College of Chemistry and Environmental Engineering,Shenzhen University,Shenzhen 518060,China [2]Research Institute of Tsinghua University in Shenzhen,Shenzhen 518057,China [3]Institute of Nuclear and New Energy Technology,Tsinghua University,Beijing 100084,China

出　　处：《Science China Materials》2020年第9期1719-1730,共12页中国科学（材料科学（英文版）

基　　金：supported by the National Natural Science Foundation of China(51673117 and 21805193);the Science and Technology Innovation Commission of Shenzhen(JSGG20160226201833790,JCYJ20170818093832350,JCYJ20170818112409808 and JSGG20170824112840518);China Postdoctoral Science Foundation(2017M622786,2017M622787 and 2019M653067)。

摘　　要：Due to the enhanced electrochemical activities,mixed metal oxides offer new and fascinating opportunities for high-performance supercapacitor electrodes.However,sluggish ionic and electronic kinetics within the electrode fundamentally limit further improvement of their electrochemical performance.To compensate for the deficiency,a flexible electrode(CNTF/Ni-Co-Mn-Mo NS/CNTN)composed of vertically-aligned areolate quaternary metal oxide nanosheets sandwiched between carbon nanotubes(CNTs)is constructed in this study,which demonstrates a unique hierarchical porous structure that can provide three-dimensional transport channels for both ions and electrons.The vertically aligned areolate quaternary metal oxide nanosheets enable increased exposed surface area and paths for ion transport,diffusion and redox reactions,resulting in an evident enhancement in electrochemical activities.Besides,the CNT networks provide improved conductivity,which can accelerate the electron transport.As a result,the flexible supercapacitor based on the CNTF/Ni-Co-Mn-Mo NS/CNTN electrode demonstrates a specific areal capacitance of 3738 m F cm^-2,corresponding to a high energy density of 1.17 m W h cm^-2,which outperforms most of the flexible devices reported recently.Additionally,excellent flexibility of up to 180°bend and superior performance stability of 87.87%capacitance retention after 10,000 charge-discharge cycles can be obtained.This unique design opens up a new way in the development of flexible energy storage devices with high performance.混合金属氧化物具有优异的电化学活性,在高性能超级电容电极领域具有广阔的应用前景.然而,电极内离子动力学和电子动力学的迟滞从根本上限制了其电化学性能的进一步提高.为了弥补这一不足,本文通过原位化学反应在自支撑碳纳米管薄膜(CNTF)表面生长四元过渡金属氧化物纳米片(Ni-Co-Mn-MoNS),并进一步在纳米片上沉积碳纳米管导电网络(CNTN),得到了具有"三明治"结构的多孔柔性电极薄膜(CNTF/Ni-Co-Mn-MoNS/CNTN).得益于高电化学活性四元金属氧化物纳米片和碳纳米管(CNT)的协同作用以及合理的分层设计,该柔性电极拥有出色的储能性能,在1molL^-1KOH中能达到15.39Fcm^-2(2243.42Fg^-1)的高比面积电容,优于大多数已报道的柔性电极.基于CNTF/Ni-CoMn-MoNS/CNTN电极的非对称柔性超级电容器拥有优异的电化学性能,其稳定的输出电压为1.5V,比电容可达3738.12mFcm^-2,对应于1.17mWhcm^-2的高能量密度.此外,超级电容器具有出色的柔韧性和稳定性,即使在180°弯曲下也能稳定工作,并且在高电流密度下经过10000次充放电循环后其比电容仍能保持87.87%.这种独特的设计为高性能柔性储能器件的发展开辟了新的方向.

关 键 词：SUPERCAPACITOR quaternary metal oxide carbon nanotube pseudocapacitive materials 

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