Exploring Li + and Na+ substitution for defect engineering in high-entropy oxides for lithium storage behavior
Ionics, 2026 (SCI-Expanded, Scopus)
- Publication Type: Article / Article
- Publication Date: 2026
- Doi Number: 10.1007/s11581-026-07301-9
- Journal Name: Ionics
- Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Aerospace Database, Chemical Abstracts Core, Compendex, INSPEC, Materials Science & Engineering Collection (ProQuest), Technology Collection (ProQuest)
- Keywords: Conversion anodes, Energy storage, High-entropy oxides, Lithium-ion batteries, Oxygen vacancies
- Open Archive Collection: AVESIS Open Access Collection
- Eskisehir Osmangazi University Affiliated: Yes
Abstract
High-entropy oxides (HEOs) are promising electrode materials for electrochemical energy storage due to their structural tunability and defect driven functionalities. Here, aliovalent substitution of Li+ and Na+ into rock-salt (MgCoNiCuZn)O is investigated. Single-phase HEOs with 15 mol% aliovalent incorporation were synthesized and confirmed by XRD and Rietveld refinement. XPS analysis revealed higher oxygen vacancy concentrations in Na-containing samples compared to Li-containing ones. Both systems exhibited comparable electrochemical behavior with high reversible capacities, while Na+ containing HEOs demonstrated slightly better rate capability and cycling stability. These results highlight that Na, owing to its abundance and low cost, can serve as a sustainable alternative to Li for defect engineering and performance optimization in HEO-based anodes. This study also opens new opportunities for designing HEO-based anodes and extending these concepts to other functional HEOs through compositional engineering.