Publication
Title
$Li_{2}Cu_{2}O(SO_{4})_{2}$: a possible electrode for sustainable Li-based batteries showing a 4.7 V redox activity vs $Li^{+}/Li^{0}$
Author
Abstract
 Li-ion batteries rely on the use of insertion positive electrodes with performances scaling with the redox potential of the 31) metals accompanying Liuptake/removal. Although not commonly studied, the Cu2+/Cu3+ redox potential has been predicted from theoretical calculations to possibly offer a high operating voltage redox couple. We herein report the synthesis and crystal structure of a hitherto-unknown oxysulfate phase, Li2Cu2O(SO4)(2), which contains infinite edgesharing CuO4 chains and presents attractive electrochemical redox activity with respect to Li+/Li, namely amphoteric characteristics. Li2Cu2O(SO4)(2) shows redox activity at 4.7 V vs Li+/Li corresponding to the oxidation of Cu2+ to Cu3+ enlisting ligand holes and associated with the reversible uptake-removal of 0.3 Li. Upon reduction, this compound reversibly uptakes similar to 2 Li at an average potential of about 2.5 V vs Li+/Li, associated with the Cu2+/Cu+ redox couple. The mechanism of the reactivity upon reduction is discussed in detail, with particular attention to the occasional appearance of an oscillation wave in the discharge profile. Our work demonstrates that Cu-based compounds can indeed be fertile scientific ground in the search for new high-energy-density electrodes.
Language
English
Source (journal)
CHEMISTRY OF MATERIALS
Publication
2015
Volume/pages
27:8(2015), p. 3077-3087
ISI
000353865800043
Full text (Publishers DOI)
UAntwerpen
 Faculty/Department Research group Publication type Subject Affiliation Publications with a UAntwerp address