Nano Today 34 (2020) 100902 Contents lists available at ScienceDirect Nano Today jou rn al h om epa ge: www.elsevier.com/locate/nanotoday Recent breakthroughs in two-dimensional van der Waals magnetic materials and emerging applications Yahya Khan a , Sk. Md. Obaidulla a , Mohammad Rezwan Habib a , Anabil Gayen a , Tao Liang a , Xuefeng Wang b , Mingsheng Xu a,c,∗ a College of Information Science & Electronic Engineering, State Key Laboratory of Silicon Materials, Zhejiang University, Hangzhou 310027, PR China b Collaborative Innovation Center of Advanced Microstructures, School of Electronic Science and Engineering, Nanjing University, Nanjing 210093, PR China c International Joint Innovation Center, Zhejiang University, Haining 314400, P.R. China a r t i c l e i n f o Article history: Received 14 February 2020 Received in revised form 5 May 2020 Accepted 27 May 2020 Keywords: Two-Dimensional Materials Magnetism Synthesis Characterizations Applications Spintronics a b s t r a c t Two-dimensional (2D) magnetism is now the attention of central demands in fundamental condensed matter physics concerning about the understanding and control of new phases. The demonstration of ferromagnetism in an atomically thin layer develops the prospects for a variety of device applica- tions of 2D van der Waals (vdW) materials. The long-range ferromagnetic ordering in 2D vdW crystals together with their fascinating electric and optical properties will lead to magnetic, magneto-electric, and magneto-optic applications. Low-power, high-speed, and ultra-compact spintronic devices, data storage, information recognition and processing, smart sensors, and quantum computing applications are highly necessary for future industrial applications. This review covers the fundamental chemical structures and synthesis methods of 2D magnetic materials, the techniques for characterizing magnetic properties, device applications and the challenges faced in this emerging field. The progress in both intrinsic and extrinsic magnetic 2D materials originated from external stimuli such as doping, defects, functionaliza- tion, and strain is emphasized. The comparison of fundamental physics, chemistry, and related issues of vdW 2D magnetic materials with other-dimensional counterparts concentrated on backgrounds is also emphasized. We focus on the design of chemical and crystal structures leading to 2D magnetism, detailed chemical and physical properties and the device applications of vdW 2D magnetism. Finally, challenges and outlooks in the realization of 2D magnetism are discussed and believed that this emerging field will excite more intensive research and provide exceptional breakthroughs in the field of spintronics. © 2020 Elsevier Ltd. 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Contents Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 Crystal structures of 2D materials related to magnetism . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 Graphene . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 h-BN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 TMDs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 Transition metal phosphorus trichalcogenides (TMPX) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 Transitional metal halides (TMH) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 Topological insulators . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 Synthesis of 2D materials . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 Top-down method . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 Mechanical exfoliation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 Liquid-phase exfoliation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6 ∗ Corresponding author. E-mail addresses: xfwang@nju.edu.cn (X. Wang), msxu@zju.edu.cn (M. Xu). https://doi.org/10.1016/j.nantod.2020.100902 1748-0132/© 2020 Elsevier Ltd. All rights reserved.