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arXiv · 2306.04257

MXene-based Ti2C/Ta2C lateral heterostructure: an intrinsic room temperature ferromagnetic material with large magnetic anisotropy

S. Özcan·B. Biel
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Abstract

(2D) lateral heterostructures (LH) combining Ti$_2$C and Ta$_2$C MXenes were investigated by means of first-principles calculations. Our structural and elastic properties calculations show that the lateral Ti$_2$C/Ta$_2$C heterostructure results in a 2D material that is stronger than the original isolated MXenes and other 2D monolayers such as germanene or MoS$_2$. The analysis of the evolution of the charge distribution with the size of the LH shows that, for small systems, it tends to distribute homogeneously between the two monolayers, whereas for larger systems electrons tend to accumulate in a region of $\sim$~6 Å around the interface. The work function of the heterostructure, one crucial parameter in the design of electronic nanodevices, is found to be lower than that of some conventional 2D LH. Remarkably, all the heterostructures studied show a very high Curie temperature (between 696 K and 1082 K), high magnetic moments %present in the ferromagnetic ground state, and high magnetic anisotropy energies. These features make (Ti$_2$C)/(Ta$_2$C) lateral heterostructures very suitable candidates for spintronic, photocatalysis, and data storage applications based upon 2D magnetic materials.

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S. Özcan, B. Biel. 2023-06-07. MXene-based Ti2C/Ta2C lateral heterostructure: an intrinsic room temperature ferromagnetic material with large magnetic anisotropy. https://arxiv.org/abs/2306.04257

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