On the Efficacy of Electrocatalysis in Nonaqueous Li-O2 Batteries
On the Efficacy of Electrocatalysis in Nonaqueous Li-O2 Batteries
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DOI：
10.1021/ja207229n
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发表时间：
2011-11-16
影响因子：
15
通讯作者：
Luntz, A. C.
中科院分区：
文献类型：
--
作者：
McCloskey, Bryan D.;Scheffler, Rouven;Luntz, A. C.
非均相电催化已经成为可再充电Li-空气电池研究中的焦点，以降低氧还原（放电）和特别是氧析出（充电）反应中的过电位。在这项研究中，我们表明，传统的阴极电催化在非水Li-O-2电池的过去的报告确实是真实的，但与电解质溶剂分解有关的气体释放是被催化的主导过程。在二甲氧基乙烷中，其中Li 2 O2形成是电化学的主要产物，使用相同的（Au，Pt，MnO 2）纳米颗粒没有观察到催化活性（与纯碳相比）。然而，析氧的起始电位仅略高于电池的开路电位，表明常规的析氧电催化可能是不必要的。
Heterogeneous electrocatalysis has become a focal point in rechargeable Li-air battery research to reduce overpotentials in both the oxygen reduction (discharge) and especially oxygen evolution (charge) reactions. In this study, we show that past reports of traditional cathode electrocatalysis in nonaqueous Li-O-2 batteries were indeed true, but that gas evolution related to electrolyte solvent decomposition was the dominant process being catalyzed. In dimethoxyethane, where Li2O2 formation is the dominant product of the electrochemistry, no catalytic activity (compared to pure carbon) is observed using the same (Au, Pt, MnO2) nanoparticles. Nevertheless, the onset potential of oxygen evolution is only slightly higher than the open circuit potential of the cell, indicating conventional oxygen evolution electrocatalysis may be unnecessary.