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Abstract Multiple principal element or high-entropy materials have recently been studied in the two-dimensional (2D) materials phase space. These promising classes of materials combine the unique behavior of solid-solution and entropy-stabilized systems with high aspect ratios and atomically thin characteristics of 2D materials. The current experimental space of these materials includes 2D transition metal oxides, carbides/carbonitrides/nitrides (MXenes), dichalcogenides, and hydrotalcites. However, high-entropy 2D materials have the potential to expand into other types, such as 2D metal-organic frameworks, 2D transition metal carbo-chalcogenides, and 2D transition metal borides (MBenes). Here, we discuss the entropy stabilization from bulk to 2D systems, the effects of disordered multi-valent elements on lattice distortion and local electronic structures and elucidate how these local changes influence the catalytic and electrochemical behavior of these 2D high-entropy materials. We also provide a perspective on 2D high-entropy materials research and its challenges and discuss the importance of this emerging field of nanomaterials in designing tunable compositions with unique electronic structures for energy, catalytic, electronic, and structural applications.
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This content will become publicly available on April 17, 2027
C16 Phase High Entropy Borides With High Magnetic Anisotropy
ABSTRACT High magnetic anisotropy materials have critical applications in numerous technology sectors, largely relying on rare‐earth and precious metals which poses major sustainability challenges. The high entropy composition space offers a vast arena for exploration of high magnetic anisotropy materials based on earth‐abundant elements. However, common high entropy alloys favor disordered cubic crystal structures whereas ordered uniaxial structures are necessary for the desirable strong magnetic anisotropy. Here we report the discovery of novel quinary borides with C16 uniaxial crystal structure and high magnetic anisotropy. Switching the easy‐plane anisotropy of binary C16 borides to easy‐axis can be achieved through a suitable mixing of Fe and Co on the transition metal sublattice. Using a combinatorial sputtering approach, we explore the wider high entropy composition space to further enhance the anisotropy of the C16 phase by incorporation of additional magnetic 3dtransition metals. Significant coercivity increase, more than two‐fold, has been observed, compared with binary and ternary transition metal borides. Density functional theory calculations support the experimental findings, predicting anisotropy approaching 107 erg/cm3, which is understood in terms of the optimized electronic structure of the high entropy borides. These results establish a promising boron‐assisted synthesis strategy to achieve strong magnetic anisotropy using earth‐abundant elements.
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- PAR ID:
- 10667532
- Publisher / Repository:
- Wiley-VCH GmbH
- Date Published:
- Journal Name:
- Advanced Materials
- Volume:
- 38
- ISSN:
- 0935-9648
- Page Range / eLocation ID:
- e16135
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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