Regulating Electronic Structure and Lithium-storage Kinetics of High-entropy Oxides via Fe-O-Ti Heterointerface Engineering

doi:10.15541/jim20260178

Abstract

Abstract: High-entropy oxides (HEOs) show great potential as anode materials for lithium-ion batteries owing to their compositional tunability, synergistic multication redox activity, and rich defect chemistry. However, their practical application is still limited by insufficient intrinsic conductivity and sluggish lithium-storage kinetics. In this work, a (FeZnCrMn)₃O₄/TiO₂ composite with tightly coupled Fe-O-Ti heterointerfaces was constructed via high-energy ball milling followed by high-temperature oxidation and air quenching. Compared with the Ti-incorporated (FeTiZnCrMn)₃O₄ control sample dominated by a spinel high-entropy oxide phase and the mechanically mixed (FeZnCrMn)₃O₄-TiO₂ control sample, the heterostructured composite exhibits superior rate capability and cycling stability, delivering a discharge capacity of 512.9 mAh·g^-1 at 5 A·g^-1. The relative peak-area ratio of oxygen-vacancy-related components in the surface O1s X-ray photoelectron spectrum of (FeZnCrMn)₃O₄/TiO₂ reaches 45%, indicating that the formation of heterointerfaces is accompanied by modulation of the surface defect environment. First-principles calculations demonstrate that Fe-O-Ti interfacial bonds induce redistribution of Fe/Ti-related orbitals near the Fermi level and interfacial charge rearrangement, while increasing the density of low-energy electronic states near the conduction-band minimum. The electronic structure reconstruction and defect modulation jointly improve interfacial charge-transfer kinetics and Li⁺ transport behavior, thereby enhancing high-rate lithium-storage performance. This work provides a reference for the heterointerface engineering of high-entropy oxide anodes.

Key words: high-entropy oxide, heterointerface engineering, Fe-O-Ti bond, lithium-storage kinetics, lithium-ion battery anodes

CLC Number:

O646

XIAO Bin, ZHU Haoran, ZOU Peng, WU Gang, XIE Zelin, SUI Yanwei. Regulating Electronic Structure and Lithium-storage Kinetics of High-entropy Oxides via Fe-O-Ti Heterointerface Engineering[J]. Journal of Inorganic Materials, DOI: 10.15541/jim20260178.

References

[1] ETACHERI V, MAROM R, ELAZARI R,et al. Challenges in the development of advanced Li-ion batteries: a review. Energy & Environmental Science, 2011, 4(9): 3243.
[2] LIU C, LI F, MA L P,et al. Advanced materials for energy storage. Advanced Materials, 2010, 22(8): E28.
[3] XIAO B, WU G, WANG T, et al. High-entropy oxides as advanced anode materials for long-life lithium-ion batteries. Nano Energy, 2022, 95: 106962.
[4] PATRA J, NGUYEN T X, TSAI C C,et al. Effects of elemental modulation on phase purity and electrochemical properties of Co-free high-entropy spinel oxide anodes for lithium-ion batteries. Advanced Functional Materials, 2022, 32(31): 2110992.
[5] CHEN R, LUO R, HUANG Y,et al. Advanced high energy density secondary batteries with multi-electron reaction materials. Advanced Science, 2016, 3(11): 1600051.
[6] ZOU B, ZHANG W, CUI Y,et al. Interfacial engineering for metal oxide/nitride nano-heterojunctions towards high-rate lithium-ion storage. Journal of Materials Chemistry A, 2022, 10(14): 7391.
[7] LIU W, PANG Y, SHI Z, et al. Ultrafast kinetics in a PAN/MgFe₂O₄ flexible free-standing anode induced by heterojunction and oxygen vacancies. ACS Applied Materials & Interfaces, 2022, 14(9): 11575.
[8] ZHANG Y, DONG P, ZHAO J,et al. Simple solution-combustion synthesis of Fe₂TiO₅ nanomaterials with enhanced lithium storage properties. Ceramics International, 2019, 45(9): 11382.
[9] WANG D, JIANG S, DUAN C,et al. Spinel-structured high entropy oxide (FeCoNiCrMn)₃O₄ as anode towards superior lithium storage performance. Journal of Alloys and Compounds, 2020, 844: 156158.
[10] ROST C M, SACHET E, BORMAN T,et al. Entropy-stabilized oxides. Nature Communications, 2015, 6: 8485.
[11] ANISIMOV V I, ARYASETIAWAN F, LICHTENSTEIN A I.First-principles calculations of the electronic structure and spectra of strongly correlated systems: the LDA+U method.Journal of Physics: Condensed Matter, 1997, 9(4): 767.
[12] GEORGE E P, RAABE D, RITCHIE R O.High-entropy alloys.Nature Reviews Materials, 2019, 4(8): 515.
[13] LEI F, SUN Y, LIU K,et al. Oxygen vacancies confined in ultrathin indium oxide porous sheets for promoted visible-light water splitting. Journal of the American Chemical Society, 2014, 136(19): 6826.
[14] GREINER M T, CHAI L, HELANDER M G,et al. Transition metal oxide work functions: the influence of cation oxidation state and oxygen vacancies. Advanced Functional Materials, 2012, 22(21): 4557.
[15] WANG S, GAO Y, MIAO S, et al. Positioning the water oxidation reaction sites in plasmonic photocatalysts. Journal of the American Chemical Society, 2017, 139(34): 11771.
[16] KWON H, YOON J S, LEE Y,et al. An array of metal oxides nanoscale hetero -n junctions toward designable and highly-selective gas sensors. Sensors and Actuators B: Chemical, 2018, 255: 1663.
[17] ZHANG N, JIANG R.Interfacial engineering of metal/metal oxide heterojunctions toward oxygen reduction and evolution reactions.ChemPlusChem, 2021, 86(11): 1586.
[18] SARKAR A, WANG Q, SCHIELE A,et al. High‐entropy oxides: fundamental aspects and electrochemical properties. Advanced Materials, 2019, 31(26): 1806236.
[19] SHEN G, ZHANG R, PAN L, et al. Regulating the spin state of Fe^III by atomically anchoring on ultrathin titanium dioxide for efficient oxygen evolution electrocatalysis. Angewandte Chemie International Edition, 2020, 59(6): 2313.
[20] HENKELMAN G, ARNALDSSON A, JÓNSSON H. A fast and robust algorithm for Bader decomposition of charge density.Computational Materials Science, 2006, 36(3): 354.