The fractions of various functional groups in graphene oxide (GO) are directly related to its electrical and chemical properties and can be controlled by various reduction methods like thermal, chemical and optical. However, a method with sufficient controllability to regulate the reduction process has been missing. In this work, a hybrid method of thermal and joule heating processes is demonstrated where a progressive control of the ratio of various functional groups can be achieved in a localized area.
View Article and Find Full Text PDFWe demonstrate a high-performance photodetector with multilayer tin diselenide (SnSe2) exfoliated from a high-quality crystal which was synthesized by the temperature gradient growth method. This SnSe2 photodetector exhibits high photoresponsivity of 5.11 × 105 A W-1 and high specific detectivity of 2.
View Article and Find Full Text PDFIn this work, we report on the hydrogen (H) sensing behavior of reduced graphene oxide (RGO)/molybdenum disulfide (MoS) nano particles (NPs) based composite film. The RGO/MoS composite exhibited a highly enhanced H response (∼15.6%) for 200 ppm at an operating temperature of 60 °C.
View Article and Find Full Text PDFHfSe field effect transistors are systematically studied in order to selectively tune their electrical properties by optimizing layer thickness and oxygen plasma treatment. The optimized plasma-treated HfSe field effect transistors showed a high on/off ratio improvement of four orders of magnitude, from 27 to 10, a field effect mobility increase from 2.16 to 3.
View Article and Find Full Text PDFWe fabricated a non-local spin valve with a thin layer of graphite with Co transparent electrodes. The spin-valve effect and spin precession were observed at room temperature. The magnitude of the mangetoresistance increases when temperature decreases.
View Article and Find Full Text PDFWe investigated the n-type doping effect of hydrazine on the electrical characteristics of a molybdenum disulphide (MoS2)-based field-effect transistor (FET). The threshold voltage of the MoS2 FET shifted towards more negative values (from -20 to -70 V) on treating with 100% hydrazine solution with the channel current increasing from 0.5 to 25 μA at zero gate bias.
View Article and Find Full Text PDFWe have fabricated a bilayer molybdenum disulphide (MoS2) transistor on boron nitride (BN) substrate and performed Raman spectroscopy and electrical measurements with this device. The characteristic Raman peaks show an upshift about 2.5 cm(-1) with the layer lying on BN, and a narrower line width in comparison with those on a SiO2 substrate.
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