Above-Room-Temperature Strong Ferromagnetism in 2D MnB Nanosheet

Yong Wang; Wei Xu; Dingyi Yang; Yu Zhang; Yongjie Xu; Zixuan Cheng; Xuke Mi; Yizhang Wu; Yan Liu; Yue Hao; Gen-Quan Han

doi:10.1021/acsnano.3c10218

Above-Room-Temperature Strong Ferromagnetism in 2D MnB Nanosheet

ACS Nano. 2023 Dec 12;17(23):24320-24328. doi: 10.1021/acsnano.3c10218. Epub 2023 Nov 27.

Authors

Yong Wang^{1

2}, Wei Xu³, Dingyi Yang^{1

4}, Yu Zhang⁵, Yongjie Xu⁶, Zixuan Cheng^{1

2}, Xuke Mi¹, Yizhang Wu⁷, Yan Liu^{1

2}, Yue Hao^{1

2}, Gen-Quan Han^{1

2}

Affiliations

¹ School of Microelectronics, Academy of Advanced Interdisciplinary Research, Xidian University, Xi'an 710071, People's Republic of China.
² Hangzhou Institute of Technology, Xidian University, Hangzhou 311200, People's Republic of China.
³ National Laboratory of Solid State Microstructures, Collaborative Innovation Center of Advanced Microstructures and Jiangsu Provincial Key Laboratory for Nanotechnology, Nanjing University, Nanjing 210093, People's Republic of China.
⁴ INRS Centre for Energy, Materials and Telecommunications, 1650 Boul. Lionel Boulet, Varennes, Québec J3X 1P7, Canada.
⁵ Department of Physics, Shaanxi University of Science and Technology, Xi'an 710021, People's Republic of China.
⁶ School of Education, Jiangsu Open University, Nanjing 210036, People's Republic of China.
⁷ Department of Applied Physical Sciences, The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27514, United States.

PMID: 38010743
DOI: 10.1021/acsnano.3c10218

Abstract

Two-dimensional (2D) room-temperature (RT) ferromagnetic materials have amassed considerable interest in the field of fundamental physics for applications in next-generation spintronic devices owing to their physical properties. However, realizing strong RT ferromagnetism and a high Curie temperature (T_C) in these 2D magnetic materials remains challenging. Herein, we develop a 2D MnB nanosheet for known 2D ferromagnets that demonstrates strong RT ferromagnetism and a record-high above-RT T_C of ∼585.9 K. Through magnetic force microscopy, clear evidence of ferromagnetic behavior is observed at room temperature. Structural characterization and density functional theory calculations further reveal that (i) after exfoliation of bulk, -OH functional groups were introduced in addition to Mn-B bonds being formed, which increases MnB nanosheet T_C to 585.9 K and (ii) the d³↑ spin configuration of Mn mainly contributed to the magnetic moment of MnB, and the hybridization between the d_xz (d_yz) and d_z² orbitals of the Mn atom provides a large contribution to magnetic anisotropy, which stabilizes the magnetic property of MnB. Our findings establish a strong experimental foundation for 2D MnB nanosheets as ideal materials for the construction of spintronic devices.

Keywords: 2D MBene; DFT calculations; MnB nanosheet; room-temperature ferromagnetism; spintronic devices.