Significant enhancement in the magnetic properties of Cr 2 Te 3 nanosheets by atom substitution doping.

Ferromagnetic Cr 2 Te 3 nanocrystals, with their high spin-orbit coupling and low symmetry, have attracted considerable attention as rare-earth-free magnetic nanomaterials due to their potential to achieve high magnetic anisotropy. However, their relatively low values of remanence ( M r ) and saturation ( M S ) magnetisation limit their energy product, making them unsuitable for practical applications. Herein, we report a straightforward one-pot heat-injection technique for the synthesis of high-remanence hexagonal Cr 2 Te 3 nanosheets by heterogeneous doping with atoms of M (M = V, Mn and Se). The doped materials provide enhanced M r and M S at an unchanged Curie temperature ( T C ), resulting in excellent hard magnetic properties. With Mn doping, the Mr of the matrix increases significantly, reaching 18.38 emu g -1 at 5 K, far exceeding the original undoped Cr 2 Te 3 nanosheets. The nearly square hysteresis loop makes it valuable for many low temperature applications. These results provide a valuable case for tuning the magnetism of ferromagnetic Cr 2 Te 3 by substitutional doping.