Transition group element doped room-temperature ferromagnetic two-dimensional material and preparation method thereof

Abstract

The invention discloses a transition group element doped room-temperature ferromagnetic two-dimensional material and a preparation method. By adopting the method, the preparation of two-dimensional V0.8Fe0.2Se2 nanosheets uniformly doped with Fe elements can be achieved. The preparation method comprises two steps: first step, a V0.8Fe0.2Se2 bulk single crystal is prepared by a chemical vapor transport method; second step, the bulk V0.8Fe0.2Se2 single crystal is thinned into a two-dimensional V0.8Fe0.2Se2 nanosheet by a liquid phase stripping method. The undoped VSe2 bulk material is nonmagnetic, and the doped two-dimensional V0.8Fe0.2Se2 nanoplatelet has room temperature ferromagnetism. The method comprises the specific steps: 1, weighing elemental single substances conforming to the molarratio and sealing the substances at one end of a quartz tube; 2, making the V0.8Fe0.2Se2 bulk single crystal grow through chemical vapor transport; 3, thinning the V0.8Fe0.2Se2 bulk single crystal into the two-dimensional V0.8Fe0.2Se2 nanosheet by using a formamide solvent and the liquid phase stripping method; 4, collecting the two-dimensional Vo.8Feo.2Se2 nanosheets stripped from the solution by centrifugation. The two-dimensional V0.8Fe0.2Se2 nanosheet prepared by the method is uniform in doping, has room-temperature ferromagnetism, and has a wide application prospect in the field of high-performance spin electronic devices.

Description

technical field [0001] The invention belongs to the technical field of nano-magnetic material preparation, and in particular relates to a room-temperature ferromagnetic two-dimensional material doped with transition group elements and a preparation method thereof. Background technique [0002] Two-dimensional transition metal chalcogenides are layered film materials with ultra-thin structures composed of several layers of atoms. Two-dimensional transition metal chalcogenides have rich physical and chemical properties, such as a wide range of electronic band gaps, including semiconductor molybdenum disulfide, tungsten disulfide, semi-metallic tungsten ditelluride, and metallic vanadium disulfide and vanadium diselenide, etc. In addition, two-dimensional transition metal chalcogenides with intrinsic ferromagnetism have attracted extensive attention. This is mainly due to the application of ultra-thin two-dimensional magnetic materials, which is expected to greatly increase t...

AI Technical Summary

Problems solved by technology

However, the Curie temperature of the above-mentioned two-dimensional magnetic materials is lower than room temperature, and it is impossible to realize the normal operation of two-dimensional spintronic devices at room temperature.

[0003] Vanadium diselenide is a metallic room-temperature magnetic two-dimensional material, but the magnetism of vanadium diselenide is closely related to the number of layers. When the number of layers is more than one, the magnetism will decrease significantly, and the magnetism will basically disappear when the number of layers is more than 10. This high-level sensitivity is detrimental to the practical application of vanadium diselenide in electronic devices

The reported hydrothermal synthesis of doped vanadium diselenide requires the use of a variety of chemical solvents. In addition to the required precursor elements such as vanadium, iron, and selenium, these solvents also contain carbon, nitrogen, oxygen, and hydrogen. Other elements will inevitably produce pollution during the reaction process, which will affect the quality and performance of the prepared doped two-dimensional material

Images