由于高安全、高功率和超长循环寿命等优点,钛酸锂负极材料近年来得到了广泛关注,基于钛酸锂负极的高性能超级电池电容器和锂离子电池也成为近年来的研究热点.本文采用化学氧化法制备了有机物正极材料聚三苯胺,并通过经典的电化学测试方...由于高安全、高功率和超长循环寿命等优点,钛酸锂负极材料近年来得到了广泛关注,基于钛酸锂负极的高性能超级电池电容器和锂离子电池也成为近年来的研究热点.本文采用化学氧化法制备了有机物正极材料聚三苯胺,并通过经典的电化学测试方法研究了其储能机理及相应的电极动力学过程.研究结果表明,该有机物正极的储能机制主要是基于阴离子的吸脱附反应,并表现出85 m A·g-1的可逆容量,且其动力学过程不受扩散控制,属于典型的赝电容行为.将该正极与钛酸锂负极结合构成了新型的电池电容体系,并对其电化学性能进行了研究,结果表明该体系具有高功率特性,且能量密度高于传统的混合型超级电容器.此外,本文还对该有机物正极的不足和实际应用中所面临的挑战做了初步分析.展开更多
The(Ca,R)FeAs_(2)(R=La,Pr,etc.)superconductors with a signature of superconductivity transition above 40 K possess a new kind of block layers that consist of zig-zag As chains.We report the electronic structure of the...The(Ca,R)FeAs_(2)(R=La,Pr,etc.)superconductors with a signature of superconductivity transition above 40 K possess a new kind of block layers that consist of zig-zag As chains.We report the electronic structure of the new(Ca,La)FeAs_(2)superconductor investigated by both band structure calculations and high resolution angle-resolved photoemission spectroscopy measurements.Band structure calculations indicate that there are four hole-like bands around the zone centerΓ(0,0)and two electron-like bands near the zone corner M(π,π)in CaFeAs_(2).In our angle-resolved photoemission measurements on(Ca0.9La0.1)FeAs_(2),we have observed three hole-like bands around theΓpoint and one electron-like Fermi surface near the M(π,π)point.These results provide important information to compare and contrast with the electronic structure of other iron-based compounds in understanding the superconductivity mechanism in the iron-based superconductors.展开更多
文摘由于高安全、高功率和超长循环寿命等优点,钛酸锂负极材料近年来得到了广泛关注,基于钛酸锂负极的高性能超级电池电容器和锂离子电池也成为近年来的研究热点.本文采用化学氧化法制备了有机物正极材料聚三苯胺,并通过经典的电化学测试方法研究了其储能机理及相应的电极动力学过程.研究结果表明,该有机物正极的储能机制主要是基于阴离子的吸脱附反应,并表现出85 m A·g-1的可逆容量,且其动力学过程不受扩散控制,属于典型的赝电容行为.将该正极与钛酸锂负极结合构成了新型的电池电容体系,并对其电化学性能进行了研究,结果表明该体系具有高功率特性,且能量密度高于传统的混合型超级电容器.此外,本文还对该有机物正极的不足和实际应用中所面临的挑战做了初步分析.
基金Supported by the National Natural Science Foundation of China under Grant No 10734120the National Basic Research Program of China under Grant Nos 2011CB921703 and 2011CB605903.
文摘The(Ca,R)FeAs_(2)(R=La,Pr,etc.)superconductors with a signature of superconductivity transition above 40 K possess a new kind of block layers that consist of zig-zag As chains.We report the electronic structure of the new(Ca,La)FeAs_(2)superconductor investigated by both band structure calculations and high resolution angle-resolved photoemission spectroscopy measurements.Band structure calculations indicate that there are four hole-like bands around the zone centerΓ(0,0)and two electron-like bands near the zone corner M(π,π)in CaFeAs_(2).In our angle-resolved photoemission measurements on(Ca0.9La0.1)FeAs_(2),we have observed three hole-like bands around theΓpoint and one electron-like Fermi surface near the M(π,π)point.These results provide important information to compare and contrast with the electronic structure of other iron-based compounds in understanding the superconductivity mechanism in the iron-based superconductors.
