Change in Magnetic Properties upon Chemical Exfoliation of FeOCl

Abstract

The development of novel, intrinsic two-dimensional (2D) antiferromagnets presents the opportunity to vastly improve the efficiency of spintronic devices and sensors. The strong intrinsic antiferromagnetism and van der Waals layered structure exhibited by the bulk transition-metal oxychlorides provide a convenient system for the synthesis of such materials. In this work, we report the exfoliation of bulk FeOCl into and subsequent characterization of intrinsically antiferromagnetic thin-layer FeOCl nanosheets. The magnetic properties of bulk FeOCl, its lithium intercalate, and its nanosheet pellet are measured to determine the evolution of magnetic properties from the three-dimensional to the quasi-two-dimensional system. This work establishes FeOCl and isostructural compounds as a source for the development of two-dimensional intrinsic antiferromagnets.

van der Waals Magnets: Material Family, Detection and Modulation of Magnetism, and Perspective in Spintronics

“…The intriguing properties of their bulk counterparts, such as metamagnetism [39] and multiferroicity, [40,41] make them possible to have marvelous characteristics at 2D limit. As predicted by CrOCl [89] Pmmn AFM Insulator 13.5 K ⊥ -TiOCl [87] Pmmn Spin-Peierls Insulator 91 K (PM-IC) 48 K (IC-sP) --TiOBr [88] Pmmn Spin-Peierls Insulator 67 K (PM-IC) 28 K (IC-sP) --VOCl [90] Pmmn AFM Insulator 80.5 K ∥ -FeOCl [ 91,96] Pmmn…”

“…c) The temperature‐dependent magnetic susceptibility measured on chemically exfoliated FeOCl nanoflakes using the field‐cooling mode (blue, magnetic field: 1T) and zero‐field‐cooling mode (orange), and the inset shows the field‐dependent magnetization measured at 2 and 300 K. Reproduced with permission. [ 96 ] Copyright 2020, American Chemical Society. d) The calculated spin‐splitting (left, where red and black denotes the majority and minority spins, respectively), nonmagnetic (middle), and the experimentally observed (right) electronic structures of monolayer VSe 2 .…”

“…[94,95] For example, the theoretically predicted T C of monolayer CrSCl and CrSeBr are both around 500 K, much higher than the predicted T C of monolayer CrOCl (≈160 K). [92,95] As for FeOCl, few-layer samples are obtained by chemical exfoliation, which display intrinsic antiferromagnetism like its bulk counterparts with a decrease of T N from 92 K (bulk) to 14 K. [96] However, according to the different temperature dependence of magnetic susceptibility in the field-cooling and zerofield-cooling modes at low temperature as well as the hysteresis at 2 K, FeOCl nanosheets are likely to possess canted antiferromagnetism ( Figure 4c). Additionally, VOCl nanoflakes are synthesized using chemical vapor deposition (CVD), and the fabricated memristive devices based on VOCl nanoflakes show their potentials in high performance electronics.…”

High-throughput computational screening for two-dimensional magnetic materials based on experimental databases of three-dimensional compounds

“…Again, we rediscover a few materials (FeTe and VBrO) that were previously predicted to be ferromagnetic from computational screening of the C2DB. FeClO has recently been exfoliated to bilayer nanoflakes and were shown to retain the antiferromagnetic ordering known from the bulk material 46 . The discrepancy with our prediction of ferromagnetic order could either be due to an inaccurate description by PBE or due to the fact that the true antiferromagnetic structure of bulk FeClO is strongly noncollinear 47 , which is not taken into account in the present simplistic calculations.…”

Iron Oxychloride/Bovine Serum Albumin Nanosheets as Chemodynamic Therapy Agents

“…To this end, some reports have used organic solvents for the production of nanosized FeOCl. [ 25–29 ] However, to make it more compatible with biological systems, the synthesis of FeOCl NSs in water as a green solvent is preferred. In our previous work, we used bovine serum albumin (BSA) as an exfoliating and stabilizing agent to achieve the NSs of FeOCl in aqueous dispersions.…”