Porous spinel-type (Al0.2CoCrFeMnNi)0.58O4-δ high-entropy oxide as a novel high-performance anode material for lithium-ion batteries

Owing to their entropy stabilization and multi-principal effect, transition-metal-based high-entropy oxides are attracting extensive attention as an effective family of anode materials for lithium ion batteries (LIBs). Herein, spinel-type (Al0.2CoCrFeMnNi)(0.58)O4-delta HEO nanocrystalline powder with high concentration of oxygen vacancies is successfully prepared by the method of solution combustion synthesis (SCS), and explored as a novel anode active material for LIBs. As compared to (CoCrFeMnNi)(0.6)O4-delta, the inactive Al3+-doped (Al0.2CoCrFeMnNi)(0.58)O4-delta anode provides more than twice the reversible specific capacity of 554 mAh g(-1) after 500 cycles at a specific current of 200 mA g(-1), accompanied with good rate capability (634 mAh g(-1) even at 3 A g(-1)) and cycling performance. The enhanced electrochemical properties can be attributed to that inactive Al3+-doping resulted into the more space for Li+ intercalation and deintercalation, enhanced structural stability, and the improved electronic conductivity and Li+ diffusivity. [GRAPHICS] .