High Entropy Oxide Duplex Yolk-Shell Structure with Isogenic Amorphous/Crystalline Heterophase as a Promising Anode...

Area of Science:

• Materials Science
• Electrochemistry
• Nanotechnology

Background:

• High entropy materials offer unique properties for energy storage applications.
• Controlling composition and structure in high entropy materials is crucial for performance enhancement.
• Developing advanced anode materials is key to improving lithium-ion battery technology.

Purpose of the Study:

• To design and synthesize a novel high entropy oxide with a duplex yolk-shell structure and isogenic amorphous/crystalline heterophase.
• To investigate the material's potential as a high-performance anode for lithium-ion batteries.
• To explore the structure-property relationships governing the material's electrochemical performance.

Main Methods:

• A microthermal solvothermal reaction was employed to create a high entropy precursor with a duplex yolk-shell structure.
• Mesothermal calcination at 450°C transformed the precursor into the target high entropy oxide.
• Electrochemical testing, including capacity measurements and cycling stability, was performed for lithium-ion battery anode evaluation.

Main Results:

• The synthesized material, (CrMnFeCoNi)3O4 (DYSHEO-450), exhibited a unique isogenic amorphous/crystalline heterophase structure.
• DYSHEO-450 demonstrated high specific capacities of 1721 mAh g⁻¹ at 0.5 A g⁻¹ and 1356 mAh g⁻¹ at 1 A g⁻¹ after 500 cycles.
• The material showed excellent capacity retention (90.3%) and promising performance in a practical coin-type full cell.

Conclusions:

• The combination of high entropy effect, duplex yolk-shell structure, and amorphous/crystalline heterophase significantly enhances lithium-ion battery anode performance.
• The developed material effectively accommodates volume expansion and reduces ion migration obstruction.
• This work presents a new strategy for structural regulation of high entropy materials for advanced energy storage solutions.