The influence of transition metal oxides on the kinetics of Li2O2oxidation in Li–O2batteries: high activity of chromium oxides

• DOI: 10.1039/c3cp53330a
• Publication Date: 2013-11-29T12:03:20Z
• Authors: Koffi P. C. Yao; Yi-Chun Lu; Chibueze V. Amanc...; David G. Kwabi; Marcel Risch; Jigang Zhou; Alexis Grimaud; Paula T. Hammond; Fanny Bardé; Yang Shao-Horn
• Keywords: Oxygen evolution; Oxidation state

Reducing the energy loss associated with Li2O2 electrochemical oxidation is paramount to development of efficient rechargeable lithium–oxygen (Li–O2) batteries for practical use. The influence a series perovskites different eg filling on kinetics was examined using Li2O2-prefilled electrodes. While LaCrO3 inactive oxygen evolution upon water in alkaline solution, it found provide highest specific current towards among all examined. Further exploration Cr-based catalysts showed that Cr nanoparticles (Cr NP) an average particle size 40 nm, having oxidized surfaces, had comparable surface area activities but much greater mass activities. Unlike Pt/C and Ru/C promote electrolyte addition oxidation, no evidence enhanced NP relative Vulcan carbon. X-ray absorption spectroscopy at O K L edge revealed redox process Cr3+ ↔ Cr6+ which might be responsible reduced charging voltages Li–O2 batteries.