Chonghai Deng

One-pot sonochemical fabrication of hierarchical hollow CuO submicrospheres

Hierarchical hollow CuO submicrospheres have been fabricated on a large scale by a facile one-pot sonochemical process in the absence of surfactants and additives. The as-prepared products were investigated by XRD, FESEM, EDX, TEM, SAED, HRTEM and BET nitrogen adsorption-desorption isotherms. The results reveal that hollow pumpkin-shaped structures possess a monoclinic phase CuO with the diameters ranging from 400 to 500 nm, and their walls with around 45 nm in thickness are composed of numerous single crystalline CuO nanoribbons with a width of about 8 nm. The BET specific surface area of the as-synthesized CuO hollow structures was measured to be 59.60 m(2)/g, and the single point adsorption total pore volume was measured to be 0.1036 cm(3)/g. A possible growth mechanism for the formation of hierarchical hollow CuO structures was proposed, which is considered to be a sonohydrolysis - oriented aggregation - Ostwald ripening process. The novel hollow CuO spherical structures may utilize applications in biosensors, photonics, electronics, and catalysts.

A FACILE SYNTHESIS OF POROUS HEMATITE NANOMATERIALS AND THEIR FAST SORPTION OF CR (VI) IN WASTEWATER

ABSTRACT Porous hematite (α-Fe 2 O 3 ) nanomaterials can be simply acquired from amorphous iron (III) hydroxide (Fe (OH) 3 ) in neutral solution by an evaporation method in an open quartz flask in a vacuum drying oven. Results show that the as-obtained α-Fe 2 O 3 particles at 180°C for 2h or so are nearly spindle in shape. Each of α-Fe 2 O 3 microspindles is made of many ultrafine α-Fe 2 O 3 nanoparticles and results in a porous structure. The as-prepared porous α-Fe 2 O 3 powders have higher surface area (~78m 2 /g) and can rapidly remove Cr (VI) ions in wastewater at room temperature. The model of the adsorption kinetic of Cr (VI) is best adapted to the pseudo second-order equation. Keywords: Hematite, Thermal evaporation, Porous structure, Removal of Cr (VI) e-mail: hfuuhan@163.com 1. For Cr (VI) -adsorption: The aqueous solutions with constant Cr (VI) INTRODUCTION The design and synthesis of various morphologies nanostructures have been important research subjects in nanoscience and nanotechnology due to their unique size and shape-dependent chemical and physical properties. Nanosturctured hematite (α-Fe

Novel perpendicularly cross-rectangular CuO architectures: Controlled synthesis, enhanced photocatalytic activity and catalytic thermal-decomposition of NH4ClO4

Novel perpendicularly cross-rectangular CuO architectures have been successfully fabricated on a large scale by a facile microwave-assisted chemical aqueous route. The as-synthesized CuO products were characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), selected area electron diffraction (SAED), high resolution transmission electron microscopy (HRTEM) and UV-vis absorption spectroscopy. An individual CuO microstructure is mainly assembled by two rectangle-shaped nanosheets with different sizes, which is perpendicularly intersected through the center. A possible formation mechanism of perpendicularly cross-rectangular CuO architectures was proposed based on the comparative experimental results. The prepared CuO nanoarchitectures exhibited excellent photocatalytic activity for the decolorization of Rhodamine B (RhB) under visible light irradiation. Simultaneously, the prepared CuO products, acting as an additive, also showed effective catalytic activity on the thermal decomposition of ammonium perchlorate (NH4ClO4).