Low-dimensional Bi2Fe4O9 nanosheets and microrods have been selectively prepared by a solvothermal method, from which the growth of the Bi2Fe4O9 crystals can be controlled by the variation of reaction conditions. Stru...Low-dimensional Bi2Fe4O9 nanosheets and microrods have been selectively prepared by a solvothermal method, from which the growth of the Bi2Fe4O9 crystals can be controlled by the variation of reaction conditions. Structure determination showed that the nanosheets are mainly exposed by {001} facets while the microrods are exposed by {110} facets. Ab- sorption spectra revealed that there are two bandgaps observed for both nanosheets (at 1.9 and 1.55 eV) and microrods (1.7 and 1.45 eV), and they both would be available for the sunlight photocatalysis e ciently due to the intensive absorption ability in a wide region. Photocatalytic investigation demonstrated that the overall photocatalytic performance of the microrods is prior to that of the nanosheets due to the variation of bandgaps and exposed facets. The present report provides a useful alternative strategy for the controlling growth of nanostructures and/or microcrystals besides the present demonstration of the Bi2Fe4O9 crystals with diflerent bandgaps and facets that would be able to tune the corresponding photocatalytic ability selectively.展开更多
Herein we report the room-temperature epitaxial growth of V203 films by laser molecule beam epitaxy. X-ray diffraction pro- files show the room-temperature epitaxial V2O3 films orient in the [ 110] direction on α-Al2...Herein we report the room-temperature epitaxial growth of V203 films by laser molecule beam epitaxy. X-ray diffraction pro- files show the room-temperature epitaxial V2O3 films orient in the [ 110] direction on α-Al2O3 (0001) substrates. Atomic force microscopy measurements reveal that the ultra-smooth surfaces with root-mean-square surface roughness of 0.11 nm and 0.28 nm for 10-nm-thick and 35-nm-thick V2O3 film, respectively. X-ray photoelectron spectroscopy results indicate the V3+ oxida- tion state in the films. Typical metal-insulator transition is observed in films at about 135 K. The resistivities at 300 K are ap- proximately 0.8 mΩ cm and 0.5 mΩ cm for 10-rim-thick and 35-nm-thick V203 film, respectively.展开更多
基金This work was supported by the National Natu-ral Science Foundation of China (No.21571166 and No.51271173) and the National Basic Research Pro- gram of China (No.2012CB922001).
文摘Low-dimensional Bi2Fe4O9 nanosheets and microrods have been selectively prepared by a solvothermal method, from which the growth of the Bi2Fe4O9 crystals can be controlled by the variation of reaction conditions. Structure determination showed that the nanosheets are mainly exposed by {001} facets while the microrods are exposed by {110} facets. Ab- sorption spectra revealed that there are two bandgaps observed for both nanosheets (at 1.9 and 1.55 eV) and microrods (1.7 and 1.45 eV), and they both would be available for the sunlight photocatalysis e ciently due to the intensive absorption ability in a wide region. Photocatalytic investigation demonstrated that the overall photocatalytic performance of the microrods is prior to that of the nanosheets due to the variation of bandgaps and exposed facets. The present report provides a useful alternative strategy for the controlling growth of nanostructures and/or microcrystals besides the present demonstration of the Bi2Fe4O9 crystals with diflerent bandgaps and facets that would be able to tune the corresponding photocatalytic ability selectively.
基金supported by the National Basic Research Program of China(Grant Nos.2010CB630704 and 2012CB921403)
文摘Herein we report the room-temperature epitaxial growth of V203 films by laser molecule beam epitaxy. X-ray diffraction pro- files show the room-temperature epitaxial V2O3 films orient in the [ 110] direction on α-Al2O3 (0001) substrates. Atomic force microscopy measurements reveal that the ultra-smooth surfaces with root-mean-square surface roughness of 0.11 nm and 0.28 nm for 10-nm-thick and 35-nm-thick V2O3 film, respectively. X-ray photoelectron spectroscopy results indicate the V3+ oxida- tion state in the films. Typical metal-insulator transition is observed in films at about 135 K. The resistivities at 300 K are ap- proximately 0.8 mΩ cm and 0.5 mΩ cm for 10-rim-thick and 35-nm-thick V203 film, respectively.