AUTHOR=Yang Kun , Ren Shuning , Huang Haishen , Wu Bo , Shen Guangxian , Zhou Tingyan , Liu Xiaoying TITLE=First-Principles Study on the Half-Metallicity of New MXene Materials Nd2NT2 (T = OH, O, S, F, Cl, and Br) JOURNAL=Frontiers in Chemistry VOLUME=9 YEAR=2022 URL=https://www.frontiersin.org/journals/chemistry/articles/10.3389/fchem.2021.832449 DOI=10.3389/fchem.2021.832449 ISSN=2296-2646 ABSTRACT=

This work systematically studied the structure, magnetic and electronic properties of the MXene materials Nd₂N and Nd₂NT₂ (T = OH, O, S, F, Cl, and Br) via first-principles calculations based on density functional theory. Results showed that Nd₂NT₂ (T = OH, O, S, F, Cl, and Br) have half-metallic characteristics whose half-metallic band gap width is higher than 1.70 eV. Its working function ranges from 1.83 to 6.50 eV. The effects of strain on its magnetic and electronic structures were evaluated. Results showed that the structure of Nd₂NT₂ (T = OH, O, S, and Br) transitions from a ferromagnetic half-metallic semiconductor to a ferromagnetic metallic and ferromagnetic semiconductor under different strains. By contrast, the structures of Nd₂NF₂ and Nd₂NS₂ were observed to transition from a half-metallic semiconductor to a ferromagnetic metallic semiconductor under different strains. Calculations of the electronic properties of different proportions of the surface functional groups of Nd₂NT_x (T = OH, O, and F; x = 0.5, 1(I, II), and 1.5) revealed that Nd₂NO_1.5 has the characteristics of semiconductors, whereas Nd₂NO(II) possesses the characteristics of half-metallic semiconductors. The other structures were observed to exhibit the characteristics of metallic semiconductors. Prediction of Nd₂NT₂ (T = OH, O, S, F, Cl, and Br) increases the types of lanthanide MXene materials. They are appropriate candidate materials for preparing spintronic devices.