Ji Peiyuan, Wan Jing, Xi Yi, Guan Yuzhu, Zhang Chengshuang, Gu Xiao, Li Jien, Lu Junlin, Zhang Dazhi
Chongqing Key Laboratory of Soft Condensed Matter Physics and Smart Materials, College of Physics, Chongqing University, Chongqing, 400044, People's Republic of China.
Nanotechnology. 2019 Aug 16;30(33):335401. doi: 10.1088/1361-6528/ab0cd1. Epub 2019 Mar 5.
One-dimensional tunnel and layer frame crystal structure materials are extremely attractive for energy storage in electrode materials. The energy storage properties of the electrode materials depend on their conductivity. Furthermore, the conductivity of electrode materials can be tailored through combination or doping with other materials, which transforms their properties from semiconductor to semimetallic or metallic and allow them to show unequaled performance for storage devices. In this work, heterostructures of manganese oxide (MnO) and modified sodium titanate (NaTiO) (MnO@NaTiO) nanowires are attained by the in situ thermal decomposition method. The heterojunction between MnO and NaTiO allows the semiconductor properties of pure NaTiO to show remarkable metallic behavior for improving the electrochemical performance. The capacitance of MnO@NaTiO heterojunction nanowires can reach 272.3 F g, a power intensity of 250 W kg at the energy density of 37.83 Wh kg and retain 5000 W kg at 6.67 Wh kg as well. The energy storage mechanism of the MnO@NaTiO heterostructure is studied by density functional theory. All of the results show that the MnO@NaTiO heterostructure material has the potential to be an excellent supercapacitor material in the future.
一维隧道和层状框架晶体结构材料对于电极材料中的能量存储极具吸引力。电极材料的储能特性取决于其导电性。此外，电极材料的导电性可通过与其他材料复合或掺杂来调整，这会将其性质从半导体转变为半金属或金属，并使其在存储设备中展现出无与伦比的性能。在这项工作中，通过原位热分解法获得了氧化锰（MnO）和改性钛酸钠（NaTiO）（MnO@NaTiO）纳米线的异质结构。MnO和NaTiO之间的异质结使纯NaTiO的半导体性质表现出显著的金属行为，从而改善了电化学性能。MnO@NaTiO异质结纳米线的电容可达272.3 F g，在能量密度为37.83 Wh kg时功率强度为250 W kg，在6.67 Wh kg时也能保持5000 W kg。通过密度泛函理论研究了MnO@NaTiO异质结构的储能机制。所有结果表明，MnO@NaTiO异质结构材料未来有潜力成为一种优异的超级电容器材料。
