Role of Fe-Doping Effect in 2-D MoS₂ Magnetic Semiconductor

Two 2-D Mo_1-xFe_xS₂ (x = 0, 0.01) nanosheets were fabricated by the hydrothermal method. X-ray diffraction shows both samples are formed in hexagonal P6₃/mmc (2H structure) phase with 2-D morphology. Raman spectra displayed that the peak widths were broadening in the iron-doped sample. AC conductivity experiments revealed that both samples obeyed the small polaron hopping model. The activation energies ofx = 0$ are 0.121(3) and 0.066(1) eV above and below 200 K. Similarly, two different activation energies, 0.140(2) and 0.082(1) eV above and below 240 K are also found inx = 0.01 sample. The effect of iron-doped may raise the activation energies of small polaron. Diamagnetism and paramagnetism were observed in pure MoS₂ and iron-doped sample, respectively. Magnetic hysteresis experiments show no loop in both samples, which is evidence that there was not any magnetic domain formed. Forx = 0.01 sample, the Brillouin function is conducted to fit the M-H curve. The fit< μ z> of thex = 0.01 sample is about 0.038(1) μ B/f. u., which matched the value of 1% Fe⁴⁺ (S = 2) ion-doped.