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[资源] Bruce最新Li-O2电池Nature chemistry，这个充电平台好平呀

The non-aqueous Li–air (O2) battery is receiving intense interest because its theoretical specific energy exceeds that of Li-ion batteries. Recharging the Li–O2 battery depends on oxidizing solid lithium peroxide (Li2O2), which is formed on
discharge within the porous cathode. However, transporting charge between Li2O2 particles and the solid electrode surface is at best very difficult and leads to voltage polarization on charging, even at modest rates. This is a significant problem
facing the non-aqueous Li–O2 battery. Here we show that incorporation of a redox mediator, tetrathiafulvalene (TTF), enables recharging at rates that are impossible for the cell in the absence of the mediator. On charging, TTF is oxidized to TTF1 at the cathode surface; TTF1 in turn oxidizes the solid Li2O2, which results in the egeneration of TTF. The mediator acts as an electron–hole transfer agent that permits efficient oxidation of solid Li2O2. The cell with the mediator demonstrated 100 charge/discharge cycles.

附注：TTF的维基百科介绍：
四硫富瓦烯（TTF），是富瓦烯的2,2'-位被硫原子替换后形成的化合物。它最早由Wudl在1970年合成，1972年发现其氯化物盐具高导电性，次年制得其TCNQ盐，并发现该盐的导电性在室温以下突然增加，在60K可达10^4 ohm^(-1) cm^(-1)，足以被称为“有机金属”。1979年又进一步发现以四硫富瓦烯为基础的Bechgaard盐[TMTSF]2X（X为PF6-,AsF6-）为首个制得的分子超导体，使得人们对这一领域产生极大兴趣。
四硫富瓦烯虽然看上去是14π的平面系统，但缺乏环状共轭，所以不具芳香性。它可被氧化为自由基阳离子及双阳离子，均是热力学稳定和具芳香性的物种，氧化反应分步且可逆。四硫富瓦烯是强π电子供体，与受体如TCNQ形成的盐类是分子导体的典型代表，此类盐具高各向异性的导电性。
http://zh.wikipedia.org/wiki/%E5 ... C%E7%93%A6%E7%83%AF[ Last edited by nihaoczh on 2013-5-13 at 08:06 ]

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