Lithia/(Ir, Li2IrO3) nanocomposites for new cathode materials based on pure anionic redox reaction.

摘要: Anionic redox reactions attributed to oxygen have attracted much attention as a new approach overcoming the energy-density limits of cathode materials. Several oxides been suggested materials with high capacities based on anionic (oxygen) reactions. Although most still large portion their capacity cationic reaction, lithia-based cathodes present that are purely dependent upon redox. Contrary Li-air batteries, other systems using pure reactions, charge and discharge without phase transition between gas condensed forms. This leads more stable cyclic performance lower overpotential compared those systems. However, activate nanolithia stabilize reaction products such Li2O2 during cycling, demand efficient catalysts (dopants). In this study, Ir (Ir Li2IrO3) were introduced (dopants) for composites. Oxide types (Li2IrO3) used source catalyst because ductile metal (Ir) can hardly be pulverized milling process. Two Li2IrO3 prepared catalyst-sources. They named ‘1-step Li2IrO3’ ‘2-step Li2IrO3’, respectively, since they by ‘1-step’ or ‘2-step’ heat treatment. The nanocomposites lithia & 2-step presented higher capacity, performance, than 1-step Li2IrO3. voltage profiles up limited 600 mAh·g−1, was maintained 100 cycles. XPS analysis confirmed our compounds is attributable whereas related barely contributes capacity.