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Highly efficient visible-light-driven WO3/Fe2(WO4)3·10.7H2O porous microplates have been fabricated for the first time by a simple one-step hydrothermal method using sodium tungstate and iron chloride as precursors. The photocatalyst was characterized by employing X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), UV-VIS absorption, photoluminescence (PL), and Fourier transform infrared spectroscopy (FTIR). From the FESEM and TEM analysis, the size of as-prepared porous microplates was estimated to be ca. 2 μm. The as-prepared sample maintained a high specific surface area (96.906 m2 g−1) and showed remarkably high photocatalytic performance (k = 0.06771 min−1) for the degradation of methyl orange (MO) under visible light irradiation. The improved performance of the product was found to be 3.3 times greater than pure WO3 and about 6.7 times greater than that of P25 TiO2. The enhanced optical absorption in the visible region, large specific surface area, suitable band position and efficient separation of photogenerated electron–hole pairs at the heterojunction interface between the two materials were the key factors involved in the enhancement of the photocatalytic activity. [ABSTRACT FROM AUTHOR]

Well controlled nanosheets-based hierarchical microspheres (NSHMS) of pure covellite phase CuS were synthesized using a facile PVP assisted solvothermal process. The reaction conditions were optimized using various amounts of PVP to develop unique hierarchical structured hollow microspheres. CuS hollow structures have a bandgap of ~1.97 eV. These mesoporous structures exhibit excellent photocatalytic activity in degradation of organic dyes (Methylene Blue) under natural light in comparison to other structures of copper sulphide. These photocatalysts show extraordinary reusability with over 96.5% degradation of organic dye after 6th cycle. A "bottom-up" assembly was successfully developed to synthesize hollow microspheres with unique and well defined architectures at large scale, which offer a good opportunity to understand the fundamental significance of unusual and complex hierarchical structures for their potential applications. [ABSTRACT FROM AUTHOR]

For the first time, high quality SnSe nanowires were synthesized via chemical vapour deposition (CVD). The synthesized SnSe nanowires are single crystalline. The length of the nanowires is in tens of microns with an average diameter of about 30-40 nm. Further, the optical and electrical properties reveal the potential of SnSe nanowires for photovoltaic and optical devices. These studies will enable significant advancements of the next generation photodetection and solar cell applications. [ABSTRACT FROM AUTHOR]

An easy, scalable and environmentally benign chemical method has been developed to synthesize micro strings of graphitic-C3N4 (msg-C3N4) through pre-treatment of melamine with HNO3 in alkaline solvent at low temperature. This methodology results in a unique string type morphology of msg-C3N4 with higher surface area. These msg-C3N4 micro strings were used as a photocatalyst under visible light for photodegradation of rhodamine B, methyl blue and methyl orange. The msg-C3N4 shows enhanced photodegradation efficiency due to its high surface area and favourable bandgap. The first order rate constant for msg-C3N4 was measured which confirms the higher performance of msg-C3N4 in comparison to other reported materials such as g-C3N4, Fe2O3/g-C3N4 and TiO2 nanotubes. Thus, the method developed here is favourable for the synthesis of materials with higher surface area and unique morphology, which are favourable for high photodegradation activity. [ABSTRACT FROM AUTHOR]

We have established a facile and scaleable approach to fabricate tubular graphitic-C3N4 using melamine. The construction of the unique tubular morphology is a result of the pre-treatment of melamine with HNO3. Herein, for the first time, we have explored the electrochemical properties of g-C3N4 as an electrode material for supercapacitors. Tubular g-C3N4 has significant advantages due to its distinctive morphology, high surface area (182.61 m2 g−1) and combination of carbon with nitrogen. Therefore, tubular g-C3N4 demonstrated a good specific capacitance of 233 F g−1 at a current density of 0.2 A g−1 in 6 M KOH electrolyte. Furthermore, tubular g-C3N4 maintained a high capacitance retention capability (90%) after 1000 cycles. The photocatalytic activity of tubular g-C3N4 was evaluated using the organic dyes such as Methylene Blue (MB) and Methylene Orange (MO) under visible light. Tubular g-C3N4 demonstrated good photocatalytic activity and enhanced stability compared to bulk g-C3N4. The enhanced performance is because of the high surface area, which contains more active sites for reaction. The encouraging performance of tubular g-C3N4 in supercapacitors and as a photocatalyst points toward it being a prospective material for energy storage that is environmentally clean. [ABSTRACT FROM AUTHOR]

Novel nanoflowers (NNF) of Nb3O7F have been synthesized by a facile template free route without using any surfactant. The evolution of these NNF have been studied by varying different reaction parameters. Using the UV-Vis spectra absorption peak the calculated bandgap was 2.9 eV. Organic dye rhodamine B (RhB) was degraded with average photodegradation efficiency of 87.8%, 94.23% and 99.7% with higher rate constant k = 1.1559, 1.9011 and 3.8862 for 0.005 g, 0.01 g and 0.1 g respectively. The rate constant for 0.1 g was found to be larger than for Nb2O5, commercial TiO2 Degussa P25, carbon modified Nb2O5/TiO2, g-C3N4, Fe2O3/g-C3N4 composites and SnNb2O6. [ABSTRACT FROM AUTHOR]