Kinetically Accelerated Lithium Storage in High-Entropy (LiMgCoNiCuZn)O Enabled By Oxygen Vacancies

High-entropy oxides (HEOs) are gradually becoming a new focus for lithium-ion battery (LIB) anodes due to their vast element space/adjustable electrochemical properties and unique single-phase retention ability. However, the sluggish kinetics upon long cycling limits their further generalization. Here, oxygen vacancies with targeted functionality are introduced into rock salt-type (MgCoNiCuZn)O through a wet-chemical molten salt strategy to accelerate the ion/electron transmission. Both experimental results and theoretical calculations reveal the potential improvement of lithium storage, charge transfer, and diffusion kinetics from HEO surface defects, which ultimately leads to enhanced electrochemical properties. The currently raised strategy offers a modular approach and enlightening insights for defect-induced HEO-based anodes.

Automated summary

High-entropy oxides (HEOs) have recently gained attention as potential anode materials for lithium-ion batteries (LIBs) due to their adjustable electrochemical properties and single-phase retention ability. However, the slow kinetics during long cycling hinders their widespread application. In this study, oxygen vacancies are introduced into rock salt-type (MgCoNiCuZn)O using a wet-chemical molten salt strategy to enhance ion and electron transmission. Experimental results and theoretical calculations demonstrate that these surface defects improve lithium storage, charge transfer, and diffusion kinetics, leading to enhanced electrochemical properties. This strategy provides a modular approach and insightful guidance for defect-induced HEO-based anodes.