Hanmei Hu

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.

Hierarchical Self-Assembly of Flower-Shaped CuO With High Photocatalysis Efficiency for Degrading Rhodamine B

Flower-shaped CuO with hierarchical microstructures was successfully synthesized through an ultrasound-assisted aqueous chemical method. The comparative experiment results show that the phase and morphology of as-obtained products are greatly affected by the volume of ammonia and the time for keeping ultrasonic irradiation, respectively. The prepared CuO microflowers assembled by nanosheets with needle-like tips exhibit a much higher activity than the commercial CuO for degrading Rhodamine B. Additionally, the photocatalytic performance of as-prepared hierarchical CuO microflowers was also evaluated through the degradation of Methylene blue and Methyl orange under the same conditions.

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).