Magnetic Moments Induced by Atomic Vacancies in Transition Metal Dichalcogenide Flakes

Abstract

Abstract2D magnetism plays a key role in both fundamental physics and potential device applications. However, the instability of the discovered 2D magnetic materials has been one main obstacle in deep research and potential application of 2D magnetism. Here, a localized magnetic moment induced by Pt vacancies in air‐stable type‐II Dirac semimetal PtSe2 flakes is reported. The localized magnetic moments give rise to the Kondo effect, evidenced by logarithmic increment of resistance with decreasing temperature and isotropic negative longitudinal magnetoresistance. Additionally, the induced magnetic moment and Kondo temperature appear to depend on thickness in the thinner samples (<10 nm). The small magnetocrystalline anisotropy revealed by first‐principles calculation indicates that the magnetic moments are randomly localized instead of long‐range ordered. The findings demonstrate a new means to induce magnetism in 2D non‐magnetic materials.

Excellent HER and OER Catalyzing Performance of Se‐Vacancies in Defects‐Engineered PtSe2: From Simulation to Experiment

“…Se defects will break the spatial symmetry of two surfaces of 1T sandwich structure PtSe 2 . Unlike the widely studied Pt defects which induce a local magnetic moment, [41][42][43][44]47,52,53] Se defects improve the electronic conductivity. [46,48] Note that some different Se defects even exhibit nearly same scanning tunneling microscope (STM) images, making the real structures of Se defects are very hard to be identified in experiment while Pt defects are relatively easy to identify.…”

“…However, studies on the structure and catalysis capacity of defects, especially multiple ones, in PtSe 2 are still rare. [41][42][43][44][45][46][47][48][49][50][51][52][53] In this paper, the structures, fractions and catalytic performance of various Se vacancies in defective PtSe 2 (d-PtSe 2 ) monolayers were investigated systematically. We indicate the point Se vacancies are quite stable once they are introduced in PtSe 2 .…”

Efficient N2- and O2-Sensing Properties of PtSe2 With Proper Intrinsic Defects

“…al. also reported the existence of magnetic moments induced by Pt vacancy defects in PtSe 2 flakes ( Ge et al, 2020 ).…”

Atomically Thin 2D van der Waals Magnetic Materials: Fabrications, Structure, Magnetic Properties and Applications

“…Their work suggested that 2D monolayer nanosheets like Mn-doped CdSe(en) 0.5 had advantages for future diluted magnetic semiconductor (DMS) applications. Recently, Ge et al reported magnetic moments induced by atomic vacancies in transition metal dichalcogenide PtSe 2 flakes, and they experimentally demonstrated the presence of nearly thickness-dependent, localized magnetic moments induced by Pt-vacancy defects in air-stable PtSe 2 flakes [207]. Their work indicated that defect control was a practical approach to induce magnetism in non-magnetic materials, offering a new way to modulate magnetism in TMDCs.…”