High Entropy Oxide Duplex Yolk–Shell Structure with Isogenic Amorphous/Crystalline Heterophase as a Promising Anode Material for Lithium‐Ion Batteries
Chunyan Zhang, Mengfei Su, Yana Luo, Xinyu Zhang, Shengfa Li, Feng Gao, Qingyi Lu
Abstract
Abstract Achieving composition and structure regulation on high entropy materials is a big challenge but will give this kind of new materials a huge boost in energy storage. Herein, a novel high entropy oxide ((CrMnFeCoNi) 3 O 4 ) duplex yolk–shell structure (DYSHEO) with isogenic amorphous/crystalline heterophase are designed and successfully prepared through a simple microthermal solvothermal reaction followed by mesothermal calcination. The microthermal solvothermal reaction results in high entropy precursor with duplex yolk–shell structure, while the mesothermal calcination (annealing temperature at 450 °C) realizes the precursor transformation to (CrMnFeCoNi) 3 O 4 (DYSHEO‐450) with isogenic amorphous/crystalline heterophase structure. The high entropy effect, the duplex yolk–shell structure, and the isogenic amorphous/crystalline heterophase endow DYSHEO‐450 great advantages as lithium‐ion battery anode including reducing ion migration obstruction, accommodating volume expansion, and alleviating the stress. Accordingly, DYSHEO‐450 exhibits high capacities of 1721 mAh g −1 @0.5 A g −1 , and 1356 mAh g −1 @1 A g −1 after 500 cycles with a capacity retention rate of 90.3%. It also shows excellent performances in practical application as anode of a coin‐type full cell. This work provides new ideas and directions for the structural regulation of high‐entropy materials.