Flower-like CuO and flower-like CuO/graphene composite were prepared successfully by hydrothermal method. They were characterized by X-ray diffraction, scanning electron microscopy, nitrogen adsorption, temperature-pr...Flower-like CuO and flower-like CuO/graphene composite were prepared successfully by hydrothermal method. They were characterized by X-ray diffraction, scanning electron microscopy, nitrogen adsorption, temperature-programmed reduction, and thermogravimetric analysis. It is found that the flower-like CuO microspheres, which are composed of CuO nanosheets, possess an average diameter of 4.2 μm and a Brunauer–Emmett–Teller surface area of 12.6 m2/g. Compared with the flower-like CuO, the obtained flower-like CuO/graphene composite shows an enhanced electrochemical performance with a higher capacity of 603 mA-h/g at 0.1 C rate and 382 mA-h/g at 1 C rate, and exhibits a better cycle stability with a high capacity retention of 95.5 % after 50 cycles even though at 1 C rate.展开更多
Flower-like 3D CuO microspheres were synthesized and used to photo-catalyze water oxidation under visible light.The structure of the CuO microspheres was characterized by scanning electron microscopy,transmission elec...Flower-like 3D CuO microspheres were synthesized and used to photo-catalyze water oxidation under visible light.The structure of the CuO microspheres was characterized by scanning electron microscopy,transmission electron microscopy,infrared,powder X-ray diffraction,electron dispersive spectroscopy,Raman and X-ray photoelectron spectroscopy（XPS）.This is the first time that a copper oxide was demonstrated as a photocatalytic water oxidation catalyst under near neutral conditions.The catalytic activity of CuO microspheres in borate buffer shows the best performance with O2 yield of 11.5%.No change in the surface properties of CuO before and after the photocatalytic reaction was seen by XPS,which showed good catalyst stability.A photocatalytic water oxidation reaction mechanism catalyzed by the CuO microspheres was proposed.展开更多
ZnO nanobelts, hollow microspheres, and urchins have been prepared on copper foil via a simply low temperature evaporation route. The microstructure, morphologies, and photolu-minescence of the ZnO nanostructures were...ZnO nanobelts, hollow microspheres, and urchins have been prepared on copper foil via a simply low temperature evaporation route. The microstructure, morphologies, and photolu-minescence of the ZnO nanostructures were studied with X-ray diffraction, Raman spectra, scanning electron microscopy and photoluminescence spectra. The width of the nanobelts was about 500 nm and the length was longer than 10μm. The diameter of the hollow microspheres was between 5 and 10μm. A possible growth mechanism of the nanobelts, microspheres and urchins was proposed. The photoluminescence spectrum exhibited strong deep level energy emissions and a weak near band edge emission. These ZnO nanostructures on a copper substrate have the advantages of naturally good adhesion and electrical connection between the ZnO nanostructures and the conductive substrate.展开更多
基金Project (20110490594) supported by China Postdoctoral Science Foundation
文摘Flower-like CuO and flower-like CuO/graphene composite were prepared successfully by hydrothermal method. They were characterized by X-ray diffraction, scanning electron microscopy, nitrogen adsorption, temperature-programmed reduction, and thermogravimetric analysis. It is found that the flower-like CuO microspheres, which are composed of CuO nanosheets, possess an average diameter of 4.2 μm and a Brunauer–Emmett–Teller surface area of 12.6 m2/g. Compared with the flower-like CuO, the obtained flower-like CuO/graphene composite shows an enhanced electrochemical performance with a higher capacity of 603 mA-h/g at 0.1 C rate and 382 mA-h/g at 1 C rate, and exhibits a better cycle stability with a high capacity retention of 95.5 % after 50 cycles even though at 1 C rate.
基金supported by the National Natural Science Foundation of China(21173105,21172098)~~
文摘Flower-like 3D CuO microspheres were synthesized and used to photo-catalyze water oxidation under visible light.The structure of the CuO microspheres was characterized by scanning electron microscopy,transmission electron microscopy,infrared,powder X-ray diffraction,electron dispersive spectroscopy,Raman and X-ray photoelectron spectroscopy（XPS）.This is the first time that a copper oxide was demonstrated as a photocatalytic water oxidation catalyst under near neutral conditions.The catalytic activity of CuO microspheres in borate buffer shows the best performance with O2 yield of 11.5%.No change in the surface properties of CuO before and after the photocatalytic reaction was seen by XPS,which showed good catalyst stability.A photocatalytic water oxidation reaction mechanism catalyzed by the CuO microspheres was proposed.
基金ACKNOWLEDGMENTS This work was supported by the Natural Science Foundation of Fujian Province of China （No.2007J0317 and No.JB06104） and the Key project of Fujian Provincial Department of Science and Technology （No.2007H0019）.
文摘ZnO nanobelts, hollow microspheres, and urchins have been prepared on copper foil via a simply low temperature evaporation route. The microstructure, morphologies, and photolu-minescence of the ZnO nanostructures were studied with X-ray diffraction, Raman spectra, scanning electron microscopy and photoluminescence spectra. The width of the nanobelts was about 500 nm and the length was longer than 10μm. The diameter of the hollow microspheres was between 5 and 10μm. A possible growth mechanism of the nanobelts, microspheres and urchins was proposed. The photoluminescence spectrum exhibited strong deep level energy emissions and a weak near band edge emission. These ZnO nanostructures on a copper substrate have the advantages of naturally good adhesion and electrical connection between the ZnO nanostructures and the conductive substrate.
