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We describe a facile approach to fabricate MoS2 and graphene oxide (GO) composites using single-step hydrothermal method to achieve excellent electrochemical properties for energy storage applications, like lithium-ion batteries. Supportive 2D structure of MoS2 material provides direct path for the electron’s flow. MoS2 and graphene oxide (GO) composites provide large surface area for intercalation of ions into/out of active materials due to their layered morphology and also minimize the path for electron transfer. The morphology of samples is studied under XRD, SEM, and TEM. The investigation confirms the formation of composites and increment in crystallinity with doping of MoS2 on graphene oxide (GO) surface. Electrochemical properties are characterized by cyclic voltammogram (CV). As a result, composite MoS2 + GO with 3% weight ratio of graphene oxide (GO) gives best cyclic stability of 740 mAh/g at low current density 100 mA/g just after 160 cycles presenting excellent improvement in electrochemical performance as electrode material in lithium-ion batteries. The structural, electronic, and optical calculations of MoS2/graphene heterostructure have been performed using the density-functional theory. The MoS2/Graphene heterostructure reveals the zero band gap due to high electronic conductivity. The calculated absorption and optical conductivity find to be high in optical properties. [ABSTRACT FROM AUTHOR]

We report a facile strategy to synthesize poly-aniline/molybdenum disulfide (PANI/MoS2) nano-composite by in situ chemical polymerization to achieve excellent electrochemical properties for application as super-capacitor electrodes. MoS2 nano-composite is prepared by a hydrothermal method and serves as an excellent 2D conductive skeleton and provides a direct path for electrons. The layered nanostructure of PANI/MoS2 composites provides a larger contact surface area for the intercalation of particles into/out of active materials and shortens the path length for electrolyte ion transport. The structure morphology is characterized by XRD, SEM, TEM and FTIR. Structural and morphological analysis reveals conformation composite formation, increase in crystallinity and particle size increased with doping by rapping of PANI on MOS2 surface. Excellent electrochemical performances of the samples are characterised and are evaluated by cyclic voltammogram, impedance and galvanostatic charge/discharge curve. The maximum specific capacitance of 453 F kg−1 at 1 Ag−1 is observed at the PANI-1%MoS2 electrodes. The energy density of 69 Wh kg−1 is obtained at a power density of 1380 W kg−1, impedance decreased from 5 Ω (PANI) to 2 Ω (1%PANI/MoS2) indicating a positive synergistic effect MoS2 and PANI for the improvement of electrochemical performance. [ABSTRACT FROM AUTHOR]

V2O3 samples were successfully prepared using [VOSO4·xH2O] as the starting material by a template-free hydrothermal method with the addition of KBrO3. The prepared samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR) and cyclic voltammetry (CV). The XRD result shows the rhombohedral structure for V2O3 with an average crystallite size in the range of 22 nm. With the increase in reaction time (6-8 h), the morphology of the samples changes from nano-flower to nano-ribbons as indicated by SEM micrographs. FTIR spectrum shows that the band at 1286 cm−1, related to C-OH stretching and OH bending vibrations and indicate the presence of residual hydroxyl groups. The electrochemical measurements show an excellent storage response, kinetics and reversibility of the electrode material. Further, good rate capability of the materials was also observed. [ABSTRACT FROM AUTHOR]

A series of single phase Y-type hexagonal ferrites having chemical formula BaZnNdFeO ( x = 0-0.1) were prepared by sol-gel technique. The X-ray diffraction patterns showed that the ferrites belong to the family of single phase Y-type hexagonal ferrites. The grain size estimated from electron microscope images confirms the crystalline nature of the investigated samples and well defined hexagonal platelet-like shape is a most suitable shape for applications. The increase in resistivity is attributed to the removal of low energy pathway due to doping cation placement at octahedral site. The enhancement in resistivity makes these materials suitable for multi-layer chip inductors. The dielectric constant decreases due to lowering of dipole moment with substitution. The frequency dependent ac conductivity increases with increase in frequency and decrease with Nd doping. The conductivity mechanism so determined was hopping mechanism. [ABSTRACT FROM AUTHOR]