Two perovskite-type fluorides K2NaVF6 and （NH4）3VF6 were synthesized under mild hydrothermal con- ditions. The structures of the compounds were determined by means of powder X-ray diffraction analysis. The Riet- vel...Two perovskite-type fluorides K2NaVF6 and （NH4）3VF6 were synthesized under mild hydrothermal con- ditions. The structures of the compounds were determined by means of powder X-ray diffraction analysis. The Riet- veld refinement indicates that K2NaVF6 has a cubic elpasolite-type structure and crystallizes in space group Fm3m with lattice constant a=8.3180（2） nm. （NH4）3VF6 has a cubic cryolite-type structure and crystallizes in space group Fm3m with lattice parameter a=9.090（1） rim. The compounds were further characterized by scanning electron micro- scopy（SEM）, thermogravimetric（TG） and differential thermal analysis（DTA）. The variable temperature magnetic susceptibility of these two compounds was characterized for the first time and the result shows that the magnetic or- dering is related to the crystallographic features and isolated magnetic unit with the temperature decreasing.展开更多
The perovskite-type AgTaO3 crystals were prepared by mild hydrothermal method and determined by powder X-ray diffraction. Rietveld refinement indicates that AgTaO3 crystallized in an orthorhombic system with the space...The perovskite-type AgTaO3 crystals were prepared by mild hydrothermal method and determined by powder X-ray diffraction. Rietveld refinement indicates that AgTaO3 crystallized in an orthorhombic system with the space group Pcmn. The lattice parameters are a=5.5822（1） nm, b=7.8522（2） nm and c=5.5347（1） nm, with α=β=γ= 90.0o. The compound was characterized by scanning electron microscopy（SEM）, X-ray photoelectron spectroscopy （XPS）, high resolution transmission electron microscopy（HR-TEM） and UV-Vis diffuse reflectance spectrometry （UV-Vis DRS）. The photocatalytic activity of AgTaO3 powder was evaluated by the degradation of Congo red under UV-light irradiation. The result shows that the titled compound has a high photocatalytic activity at room temperature and potential application in photocatalysis.展开更多
基金Supported by the Science and Technology Development Planning of Jilin Province,China(Nos.20100116,201105005)the Specialized Research Fund for the Doctoral Program of Higher Education of China(No.20100061120089)+1 种基金the Open Project of State Key Laboratory of Inorganic Synthesis and Preparative Chemistry(No.2011-01)the Open Project of State Key Laboratory of Superhard Materials(No.2011-04),China
文摘Two perovskite-type fluorides K2NaVF6 and （NH4）3VF6 were synthesized under mild hydrothermal con- ditions. The structures of the compounds were determined by means of powder X-ray diffraction analysis. The Riet- veld refinement indicates that K2NaVF6 has a cubic elpasolite-type structure and crystallizes in space group Fm3m with lattice constant a=8.3180（2） nm. （NH4）3VF6 has a cubic cryolite-type structure and crystallizes in space group Fm3m with lattice parameter a=9.090（1） rim. The compounds were further characterized by scanning electron micro- scopy（SEM）, thermogravimetric（TG） and differential thermal analysis（DTA）. The variable temperature magnetic susceptibility of these two compounds was characterized for the first time and the result shows that the magnetic or- dering is related to the crystallographic features and isolated magnetic unit with the temperature decreasing.
基金Supported by the Science and Technology Development Planning of Jilin Province, China(Nos.20100116, 201105005)the Specialized Research Fund for the Doctoral Program(SRFDP) of Higher Education of China(No.20100061120089)+1 种基金the Open Project of State Key Laboratory of Inorganic Synthesis and Preparative Chemistry of China (No.2011-01)the Open Project of State Key Laboratory of Superhard Materials of China(No.2011-04)
文摘The perovskite-type AgTaO3 crystals were prepared by mild hydrothermal method and determined by powder X-ray diffraction. Rietveld refinement indicates that AgTaO3 crystallized in an orthorhombic system with the space group Pcmn. The lattice parameters are a=5.5822（1） nm, b=7.8522（2） nm and c=5.5347（1） nm, with α=β=γ= 90.0o. The compound was characterized by scanning electron microscopy（SEM）, X-ray photoelectron spectroscopy （XPS）, high resolution transmission electron microscopy（HR-TEM） and UV-Vis diffuse reflectance spectrometry （UV-Vis DRS）. The photocatalytic activity of AgTaO3 powder was evaluated by the degradation of Congo red under UV-light irradiation. The result shows that the titled compound has a high photocatalytic activity at room temperature and potential application in photocatalysis.
