Engineering phase transitions or finding new polymorphs offers tremendous opportunities for developing functional materials. We reveal that the thermally driven desulfurization of single-crystalline MoS2 samples improves transport properties by reducing the band gap and further induces metallization. Semi-desulfurization, i.
View Article and Find Full Text PDFIdentifying and designing defects are critical steps in the development of a semiconductor. We unveil that a sufficiently high concentration of the sulfur-vacancy defect on the MoS2 surface induces an occupied defect state in the electronic band structures, in addition to the in-gap defect states. The occupied defect state is expected to appear above and below the valence band maximum (VBM) of the mono- and bilayer or bulk band structures of MoS2, respectively.
View Article and Find Full Text PDFWe provide a new insight that the sulphur-depleted MoS surface can store hydrogen gas at room temperature. Our findings reveal that the sulphur-vacancy defects preferentially serve as active sites for both hydrogen chemisorption and physisorption. Unexpectedly the sulphur vacancy instantly dissociates the H molecules and strongly binds the split hydrogen at the exposed Mo atoms.
View Article and Find Full Text PDFStrong perpendicular magnetocrystalline anisotropy (MCA) and low saturation magnetization are found in DO22Mn(3)Ga using the full-potential linearized augmented plane wave (FLAPW) method. The ferrimagnetism in the bulk is well preserved in the surfaces of Mn(3)Ga for two possible terminations, where the perpendicular MCA in the (001) direction is greatly enhanced over the bulk, consistent with experiments. Furthermore, the robustness of MCA with respect to lattice strain and a good lattice match with popular substrates suggest that Mn(3)Ga can be a good candidate for strain-resistance spintronics applications.
View Article and Find Full Text PDFPhototransistors based on multilayer MoS(2) crystals are demonstrated with a wider spectral response and higher photoresponsivity than single-layer MoS(2) phototransistors. Multilayer MoS(2) phototransistors further exhibit high room temperature mobilities (>70 cm(2) V(-1) s(-1) ), near-ideal subthreshold swings (~70 mV decade(-1) ), low operating gate biases (<5 V), and negligible shifts in the threshold voltages during illumination.
View Article and Find Full Text PDFWe report on the discovery of a room-temperature ferromagnetic semiconductor in chalcopyrite (Zn1-xMnx)GeP2 with Tc = 312 K. We have also observed that, at temperatures below 47 K, samples for x = 0.056 and 0.
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