Zhang Shiyu, Nava Matthew J, Chow Gary K, Lopez Nazario, Wu Gang, Britt David R, Nocera Daniel G, Cummins Christopher C
Department of Chemistry , Massachusetts Institute of Technology , 77 Massachusetts Avenue , Cambridge , MA 02139-4307 , USA . Email:
Department of Chemistry , University of California , Davis, One Shields Avenue , Davis , CA 95616 , USA.
Chem Sci. 2017 Sep 1;8(9):6117-6122. doi: 10.1039/c7sc01230f. Epub 2017 Jun 20.
When solubilized in a hexacarboxamide cryptand anion receptor, the peroxide dianion reacts rapidly with CO in polar aprotic organic media to produce hydroperoxycarbonate (HOOCO) and peroxydicarbonate (OCOOCO). Peroxydicarbonate is subject to thermal fragmentation into two equivalents of the highly reactive carbonate radical anion, which promotes hydrogen atom abstraction reactions responsible for the oxidative degradation of organic solvents. The activation and conversion of the peroxide dianion by CO is general. Exposure of solid lithium peroxide (LiO) to CO in polar aprotic organic media results in aggressive oxidation. These findings indicate that CO must not be introduced in conditions relevant to typical lithium-O cell configurations, as production of HOOCO and OCOOCO during lithium-O cell cycling will lead to cell degradation oxidation of organic electrolytes and other vulnerable cell components.
当过氧化物二价阴离子溶解在六羧酰胺穴醚阴离子受体中时,它会在极性非质子有机介质中与一氧化碳迅速反应,生成氢过氧碳酸盐(HOOCO)和过氧二碳酸盐(OCOOCO)。过氧二碳酸盐会发生热分解,生成两当量的高活性碳酸根自由基阴离子,这会促进氢原子夺取反应,导致有机溶剂发生氧化降解。一氧化碳对过氧化物二价阴离子的活化和转化具有普遍性。在极性非质子有机介质中,将固体过氧化锂(LiO)暴露于一氧化碳会导致剧烈氧化。这些发现表明,在与典型锂氧电池配置相关的条件下,绝不能引入一氧化碳,因为在锂氧电池循环过程中生成HOOCO和OCOOCO会导致电池降解——有机电解质和其他易损电池组件发生氧化。