Abstract
O3-type layered oxide cathodes have been widely investigated due to their high reversible capacities and sufficient Na+reservoirs.However,such materials usually suffer from complex multistep phase transitions along with drastic volume changes,leading to the unsatisfied cycle performance.Herein,we report a Mg/Ti co-doped O3-type NaNi0.5Mn0.5O2,which can effectively suppress the complex multistep phase transition and realize a solid-solution reaction within a wide voltage range.It is confirmed that,the Mg/Ti co-doping is beneficial to enhance the structural stability and integrity by absorbing micro-strain and distortions.Thus,the as obtained sample delivers an outstanding cyclic performance(82.3％after 200 cycles at 1 C)in the voltage range of 2.0-4.0V,and a high discharge capacity of 86.6 mAh/g after 100 cycles within the wide voltage range(2.0-4.5V),which outperform the existing literatures.This co-doping strategy offers new insights into high performance O3-type cathode for sodium ion batteries.
基金项目
国家自然科学基金(22179077)
国家自然科学基金(51774251)
国家自然科学基金(21908142)
Shanghai Science and Technology Commission's" Science and Technology Innovation Action Plan"(2020)(20511104003)
Natural Science Foundation in Shanghai(21ZR1424200)
维普
万方数据