Electrochimica Acta, Vol.317, 594-603, 2019
Preparation of MnO2-Cr2O3 mesoporous oxide and its application for an active and reversible air catalyst for Li-O-2 batteries
Preparation of highly porous MnO2 and Cr2O3 with regular structure was investigated in this study by using hard template method. Cr2O3 nanoarchitects with regular pore structure and alpha-MnO2 with porous nanosheet were successfully prepared. By mixing with single wall carbon nanotube (SWCNT), application of MnO2, Cr2O3 nano architects (Mn-Cr oxides supported SWCNT) was studied as active air electrode for Li-O-2 battery which is now expecting as a new rechargeable battery with large capacity. It was found that the synergy effects between two mesoporous metal oxides with SWCNT resulted in excellent electrochemical properties of air electrode. Prepared Mn-Cr oxide supported SWCNT can sustain stable charge and discharge capacity up to 150 cycles with 500 mAh/g without capacity degradation indicating outstanding catalytic activity for oxygen reduction and evolution reaction (ORR/OER). Consecutive cyclic voltammetry tests also showed excellent reversibility of formation and decomposition of reaction products of Li2O2. This could be resulted from large pore volume and ordered structure of Cr2O3 , MnO2/SWCNT air electrode. (c) 2019 Elsevier Ltd. All rights reserved.