Tunable oxygen defect density and location for enhancement of energy storage

作     者：Jun Chen Jiangao Li Ling Sun Zhong Lin Zhengguang Hu Hongtao Zhang Xiaoling Wu Dongbo Zhang Guoan Cheng Ruiting Zheng Jun Chen;Jiangao Li;Ling Sun;Zhong Lin;Zhengguang Hu;Hongtao Zhang;Xiaoling Wu;Dongbo Zhang;Guoan Cheng;Ruiting Zheng

作者机构：Key Laboratory of Radiation Beam Technology and Materials Modification of the Ministry of EducationCollege of Nuclear Science and TechnologyBeijing Normal University100875 BeijingChina Department of PhysicsNanchang UniversityNanchang 330031China Department of MaterialsLoughborough UniversityLE113TU LeicestershireUK Beijing Computational Science Research Center100193 BeijingChina 

出 版 物：《Journal of Energy Chemistry》 (能源化学（英文版）)

年 卷 期：2021年第30卷第8期

页      面：736-747,I0015页

核心收录：

学科分类：081702[工学-化学工艺] 080801[工学-电机与电器] 0808[工学-电气工程] 07[理学] 070205[理学-凝聚态物理] 08[工学] 0817[工学-化学工程与技术] 080501[工学-材料物理与化学] 0805[工学-材料科学与工程（可授工学、理学学位）] 0702[理学-物理学] 

基　　金：supported by the National Nature Science Foundation of China(11575025,U1832176) the Science and Technology Project of Beijing(Z171100002017008) the Fundamental Research Funds for the Central Universities 

主　　题：Oxygen defects Excess electrons Supercapacitors Lithium-ion batteries DFT calculations 

摘      要：Defect engineering is in the limelight for the fabrication of electrochemical energy storage ***,determining the influence of the defect density and location on the electrochemical behavior remains ***,self-organized TiO_(2)nanotube arrays(TNTAs)are synthesized by anodization,and their oxygen defect location and density are tuned by a controllable post-annealing *** annealed at 600℃ in N2 exhibit the highest capacity(289.2 m Ah g^(-1)at 0.8 C)for lithium-ion storage,while those annealed at 900℃ in N2 show a specific capacitance of 35.6 m F cm^(-2)and stability above96%after 10,000 cycles for *** situ electron paramagnetic resonance spectra show that the surface-exposed oxygen defects increase,but the bulk embedded oxygen defects decrease with increasing annealing *** functional theory simulations reveal that a higher density of bulk oxygen defects corresponds to higher localized electrons states,which upshift the Fermi level and facilitate the lithium intercalation kinetic ***,differential charge density calculation indicates that the increase of surface oxygen defects in the anatase(101)plane leads to higher density excess electrons,which act as negative charge centers to enhance the surface potential for ion *** oxygen-deficient location and density tunable strategy introduce new opportunities for high-energy and high-power-density energy storage systems.