Phase-Controlled Electrochemical Activity of Epitaxial Mg-Spinel Thin Films.
نویسندگان
چکیده
We report an approach to control the reversible electrochemical activity (i.e., extraction/insertion) of Mg(2+) in a cathode host through the use of phase-pure epitaxially stabilized thin film structures. The epitaxially stabilized MgMn2O4 (MMO) thin films in the distinct tetragonal and cubic phases are shown to exhibit dramatically different properties (in a nonaqueous electrolyte, Mg(TFSI)2 in propylene carbonate): tetragonal MMO shows negligible activity while the cubic MMO (normally found as polymorph at high temperature or high pressure) exhibits reversible Mg(2+) activity with associated changes in film structure and Mn oxidation state. These results demonstrate a novel strategy for identifying the factors that control multivalent cation mobility in next-generation battery materials.
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عنوان ژورنال:
- ACS applied materials & interfaces
دوره 7 51 شماره
صفحات -
تاریخ انتشار 2015