Monoclinic Cu3V2O7(OH)2·2H2O(copper polyvanadate) hollow spheres were prepared with Na2V6O16·3H2O nanobelts as V-precursor by hydrothermal method. The purity and structure of the products were characteri...Monoclinic Cu3V2O7(OH)2·2H2O(copper polyvanadate) hollow spheres were prepared with Na2V6O16·3H2O nanobelts as V-precursor by hydrothermal method. The purity and structure of the products were characterized by X-ray powder diffraction(XRD), Fourier transform infrared(FTIR) spectroscopy, Raman spectroscopy, thermogravimetric analysis(TGA) and X-ray photoelecton spectroscopy(XPS). The morphology and size were observed by scanning electron microscopy(SEM). We found that the Kagomé staircase-structural copper polyvanadate hollow spheres with an average diameter of 7 μm could be easily synthesized via the reaction of Na2V6O16·3H2O nanobelts with sufficient copper sulfate. The dielectric property of the copper polyvanadate demonstrates that dielectric loss hardly changes when the frequency of applied electric field is higher than 100 kHz. The formation process of the hollow spheres is discussed in detail by the observation of a series of products prepared for different reaction time.展开更多
A facile preparation of nitrogen-doped β-TiO2(N-doped β-TiO2) nanobelts and their visible-light photocatalytic activity were reported.The preparation of N-doped β-TiO2 nanobelts consisted of cation-exchange betwe...A facile preparation of nitrogen-doped β-TiO2(N-doped β-TiO2) nanobelts and their visible-light photocatalytic activity were reported.The preparation of N-doped β-TiO2 nanobelts consisted of cation-exchange between layered sodium titanate nanobelts and NH 4 + in aqueous solution at room temperature and subsequent calcination in air.Such a calcination treatment is beneficial to the formation of monoclinic N-doped β-TiO2 nanobelts.Various measurement results indicate that not only were the nitrogen atoms doped into the lattice of β-TiO2 nanobelts resulting in a strong visible-light absorption,but also a large number of defects were caused by them in the lattice,increasing the stability of β-TiO2.The photocatalysis enhancement of N-doped β-TiO2 nanobelts for the photodegradation of Rhodamine B was demonstrated.展开更多
The de magnetization of Y-type zeolite containing Fe ions and that after reduction treatment were measured in the temperature range of 1.5-300K.The samples show paramagnetic behavior・The obtained value for the magneti...The de magnetization of Y-type zeolite containing Fe ions and that after reduction treatment were measured in the temperature range of 1.5-300K.The samples show paramagnetic behavior・The obtained value for the magnetic moment of the paramagnetic units strongly implies the existence of ferromagnetic coupling between the Fe ion at site I in hexagonal prism and the one at the nearest site I' in β cage.展开更多
基金Supported by the "973" Basic Research Foundation of China(No.2006CB932605)the National Natural Science Founda-tion of China(No.20876002).
文摘Monoclinic Cu3V2O7(OH)2·2H2O(copper polyvanadate) hollow spheres were prepared with Na2V6O16·3H2O nanobelts as V-precursor by hydrothermal method. The purity and structure of the products were characterized by X-ray powder diffraction(XRD), Fourier transform infrared(FTIR) spectroscopy, Raman spectroscopy, thermogravimetric analysis(TGA) and X-ray photoelecton spectroscopy(XPS). The morphology and size were observed by scanning electron microscopy(SEM). We found that the Kagomé staircase-structural copper polyvanadate hollow spheres with an average diameter of 7 μm could be easily synthesized via the reaction of Na2V6O16·3H2O nanobelts with sufficient copper sulfate. The dielectric property of the copper polyvanadate demonstrates that dielectric loss hardly changes when the frequency of applied electric field is higher than 100 kHz. The formation process of the hollow spheres is discussed in detail by the observation of a series of products prepared for different reaction time.
基金Supported by the National Basic Research Program of China(No.2006CB932605)the National Natural Science Foundation of China(No.20876002)the Fund of Beijing Technology and Business University for the Talent,China
文摘A facile preparation of nitrogen-doped β-TiO2(N-doped β-TiO2) nanobelts and their visible-light photocatalytic activity were reported.The preparation of N-doped β-TiO2 nanobelts consisted of cation-exchange between layered sodium titanate nanobelts and NH 4 + in aqueous solution at room temperature and subsequent calcination in air.Such a calcination treatment is beneficial to the formation of monoclinic N-doped β-TiO2 nanobelts.Various measurement results indicate that not only were the nitrogen atoms doped into the lattice of β-TiO2 nanobelts resulting in a strong visible-light absorption,but also a large number of defects were caused by them in the lattice,increasing the stability of β-TiO2.The photocatalysis enhancement of N-doped β-TiO2 nanobelts for the photodegradation of Rhodamine B was demonstrated.
基金Supported by the National Natural Science Foundation of ChinaNational Fundamental Science Research Program.
文摘The de magnetization of Y-type zeolite containing Fe ions and that after reduction treatment were measured in the temperature range of 1.5-300K.The samples show paramagnetic behavior・The obtained value for the magnetic moment of the paramagnetic units strongly implies the existence of ferromagnetic coupling between the Fe ion at site I in hexagonal prism and the one at the nearest site I' in β cage.