Novel room-temperature ferromagnetism in Gd-doped 2-dimensional Ti3C2Tx MXene semiconductor for spintronics

Two-dimensional nanosheets of MXene (Ti3C2) and Gd+3-doped MXene (Ti3C2) have been synthesized superficially by using the cost-effective co-precipitation method. The hexagonal crystal structure doped by Gd was confirmed using X-ray Diffraction. The doping was further confirmed by using scanning electron microscopy, energy dispersive X-ray spectroscopy and Fourier transformed infra-red spectroscopy. Furthermore, UV-Vis spectroscopy absorption spectra, followed by a Tauc-plot, revealed a band-gap value of 1.93 eV for Gd-doped MXene, reduced from that for pure MXene (2.06 eV). The magnetic measurement of undoped and doped MXene indicate a clear ferromagnetic hysteresis existing at room-temperature. The asymmetric spatial spin-density of states (s-DOS) for undoped MXene is attributed to the existence of spin-up and spin-down electrons of Ti-3d atoms at top and bottom Titanium layers. The strength of one of the spin-type (spin-up) increases more than two-folds at room-temperature after the doping of Gd+3 cations due to the fact that it contains more unpaired electrons around Fermi level making the MXene more ferromagnetic. The present report establishes the existence of ferromagnetism introduced by doping of Gd+3 cation in Ti3C2 MXene at room-temperature making it a suitable candidate for two-dimensional spintronic devices operating at room-temperature.