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Nanourchin VO2 nanostructures have been effectively synthesized by hydrothermal method. The synthesized hierarchical nanostructure has been characterized by various characterization techniques and electrochemical behaviour has been studied. X-ray diffraction analysis revealed the monoclinic phase and morphological analysis (FESEM) of VO2 showed nanourchin-like structure with arrangement of various nanorods in radial fashion. Over these nanorods, formation of secondary growth of asterisk-shape structure was observed. The width and length of nanorods were ~ 50 and ~ 75 nm, respectively. For the electrochemical measurements, 2032 type coin cells were fabricated using VO2 as electrode material. The electrochemical study of VO2 exhibited the pseudocapacitive behaviour with specific capacitance of 44 F g−1 in organic electrolyte with symmetric capacitor of two electrode system. The maximum energy density and power density were 44 and 8635 Wh kg−1, respectively. Cycling performance exhibited symmetric charge–discharge curves, and also specific capacitance was maintained up to 82% of initial value. [ABSTRACT FROM AUTHOR]

The ABO3 type perovskite oxide‐based ceramic membranes are one of the most important classes of materials for high‐temperature solid oxide fuel cell applications. The acceptor‐doped calcium titanate (CaTiO3) perovskite has attracted considerable attention as an oxide ion‐conducting membrane due to its potentially high ionic conductivity and excellent stability. Nonetheless, the ionic conductivity of the material must still be improved. Following the strategy of the substitution of dopants on the B‐site, the current work is focused on exploring the effect of Al and Ni additions on electrical properties, by studying the nominal compositions CaTi0.7Al0.3–xNixO3−δ (x = 0, 0.1, 0.2 and 0.3). The materials were synthesized by the sol–gel method and studied as a function of phase composition, microstructure, and electrical properties. The results demonstrate an increase of both total and specific grain boundary conductivity with increasing Ni content, while predominant p‐type behavior is shown under oxygen‐rich atmosphere. [ABSTRACT FROM AUTHOR]

Graphite is considered as an ideal anode material for lithium-ion battery (LIB) due to its high stability, good conductivity and wide source of availability. However, the low energy density and theoretical capacity of graphite cannot meet the needs of high performance anode materials. To circumvent this issue, alternative materials have been sought for many years now. Herein, we report the synthesis of highly crystalline lithium iron molybdate LiFe(MoO4)2 by combustion method and evaluated its performance as an anode material for lithium-ion batteries. Triclinic LiFe(MoO4)2 crystals having particle size 2–5 μm with good crystallinity were obtained. The material shows long cycle life and high rate performance than commercial graphite and exhibits first reversible discharge capacity of 931.6 mAh/g at a current density of 100 mA/g which is three times higher than commercial graphite. The high specific capacity together with the outstanding rate and cycle performance makes LiFe(MoO4)2 a promising anode material for LIB. A detailed analysis on the crystal structure and electronic properties of LiFe(MoO4)2 is presented based on DFT studies to complement the experimental observations. [ABSTRACT FROM AUTHOR]

Mesoporous nanoparticles have a larger surface area and therefore, suitable for dye‐sensitised solar cells and photocatalytic applications. This Letter presents the analysis of solvothermal derived as‐prepared TiO2 and doped TiO2 nanocrystals by utilising acetone as the solvent. The as‐prepared and doped TiO2 nanoparticles endorsed the presence of anatase phase along with the slightly deviated diffraction peaks with the reduced crystallite size as a result of doping. Surface morphology analyses evidenced the mesoporous microspheres of nanoparticles, whereas the stoichiometry study exhibited the elementary peaks in the as‐prepared and doped samples. The estimated optical bandgaps are found to be 2.68, 2.92, 2.48 and 2.88 eV in accordance with the doped TiO2 with copper, tin, barium and zinc–magnesium as compared to 3.16 eV of TiO2. Doped samples evidenced the enhanced scattering capability, whereas tin and zinc–magnesium co‐doped samples demonstrated the highest diffuse reflectance in a broad wavelength range from 550 to 800 nm. [ABSTRACT FROM AUTHOR]

The three-dimensional hierarchical SrS/Bi2S3 heterostructures were synthesized by a template-free single-step hydrothermal method. The structural and morphological studies revealed the formation of a single crystalline orthorhombic heterostructure with rod-like morphologies possessing a high aspect ratio. The field emission properties of SrS/Bi2S3 nanorods were investigated. J-E and the Fowler-Nordheim (F-N) plot, as well as long-term field emission (FE) stability, were studied. SrS/Bi2S3 nanoflowers have enhanced the FE properties more than the virgin Bi2S3. The observed values of the re-producible turn-on field for SrS/Bi2S3 defined to draw an emission current density of ca. 1 μA/cm² were found to be ca. 2.50 V/μm, and of the threshold field to draw a current density of ca. 10 μA/cm² were found to be ca. 3.00 V/μm (without visible light illumination). A maximum emission current density of ca. 527 μA/cm² was drawn without light and a current density of ca. 1078 μA/cm² with light, which is higher than that of pristine Bi2S3. [ABSTRACT FROM AUTHOR]