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Multi-state electromagnetic phase modulations in NiCo2O4 through cation disorder and hydrogenation
Xuanchi Zhou1,2, Xiaohui Yao1, Shuang Li1
1Key Laboratory of Magnetic Molecules and Magnetic Information Materials of Ministry of Education & School of Materials Science and Engineering, Shanxi Normal University, Taiyuan, 030031, China. xuanchizhou@sxnu.edu.cn.
Materials Horizons
|June 22, 2026
Summary
Researchers explored nickel cobaltite (NiCo2O4) for oxide spintronics. They discovered that controlling cation disorder and hydrogen content enables multi-state electromagnetic phase modulations, advancing spintronic device design.
Area of Science:
- Materials Science
- Condensed Matter Physics
- Nanotechnology
Background:
- Developing low-power, scalable oxide spintronic devices requires ferromagnetic oxides with perpendicular magnetic anisotropy (PMA) and tunable spin states.
- Spinel nickel cobaltite (NiCo2O4, NCO) is a promising candidate due to its ferrimagnetic metallic nature and strong PMA.
Purpose of the Study:
- To investigate multi-state electromagnetic phase modulations in NiCo2O4.
- To explore the role of cation disorder and proton evolution in tuning NCO's electromagnetic properties for spintronics.
Main Methods:
- Controlled synthesis of NiCo2O4 with varying cation disorder.
- Investigated proton evolution and its correlation with cation disorder.
- Analyzed structural phase transformations and electromagnetic state changes induced by hydrogen incorporation.
Main Results:
- Demonstrated controllable cation disorder as a key parameter for kinetically driving proton evolution in NCO.
- Revealed emergent intermediate hydrogenated states and reversible structural/electromagnetic phase transformations.
- Observed rich spin-dependent correlated physics associated with hydrogen incorporation.
Conclusions:
- NiCo2O4 serves as a versatile platform for discovering novel spin-dependent functionalities.
- The findings expand the electromagnetic phase diagram of NCO and offer new avenues for materials design in spintronics.
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