Room-temperature ferromagnetism enhancement in Fe-doped VSe2nanosheets synthesized by a chemical method

Two-dimensional(2 D)few-layerVSe_(2),V_(1-x)Fe_(x)Se_(2) nanosheets have been synthesized by a hightemperature organic solution-phase method. The thickness of VSe_(2) nanosheets can be tuned from 12 to 5 layers by decreasing the precursor concentrations. The few-layer VSe_(2) nanosheets show the room-temperature ferromagnetism. The coercivity and magnetization reach 0.024 T and 0.036 mA·m^(2)·g^(-1) at room temperature. The chargedensity wave behavior is also confirmed in VSe_(2) by the hysteresis loops and zero-field-cooling curve. V_(1-x)Fe_(x)Se_(2) nanosheets can be obtained by doping Fe(acac)3 in the reaction process. The room-temperature coercivity and magnetization of V_(0.8)Fe_(0.2)Se_(2) nanosheets are 5 times higher than those of the pure VSe_(2) nanosheets without destroying the structures. The enhancement of magnetization is due to the coupling interaction of 3 d orbits between V and Fe atoms. Higher Fe concentration is beneficial to improve the coercivity, which is attributed to the formation of the second phase Fe3 Se4. This simple chemical preparation method can be extended to prepare the other 2 D materials.