In this paper, thermoluminescence （TL） properties of rare earth Tb^3＋-doped α-Sr2P2O7 were examined after β-irradiation and photoluminescence （PL） properties of samples were examined for proper excitation. All ...In this paper, thermoluminescence （TL） properties of rare earth Tb^3＋-doped α-Sr2P2O7 were examined after β-irradiation and photoluminescence （PL） properties of samples were examined for proper excitation. All the samples were synthesized by high-temperature combustion method. The X-ray diffraction （XRD） and Fourier transform infrared （FTIR） spectroscopy characterization confirms the formation of pure α-phase with crystallized in orthorhombic structure of samples. The PL emission spectra of all samples exhibit characteristic green emission peaks of Tb^3＋ where the peak at 545 nm has the highest emission intensity for Tb^3＋ con- centration of 5.0 mol%. The TL glow curves of β-irradiated Tb^3＋-doped α-Sr2P2O7 phosphors were recorded at different heating rates of 2, 4, and 6 K.s^-1. TL curves of all sample exhibit combination of two peaks： peak at 420 K shifts toward higher 525 K remains unaffected temperature, while peak at with the increase in Tb^3＋ concentration as well as fading effect. The activation energy and kinetic parameters of the samples were evaluated using thermoluminescence peak shape method.展开更多
The Eu(Ⅲ)nitrate complex of the meso-N,N’-bis(2-pyridylmethylene)-1,2-(R,S)-cyclohexanediamine ligand was synthesized and characterized by single crystal and powder X-ray diffraction.The crystal lattice of the compl...The Eu(Ⅲ)nitrate complex of the meso-N,N’-bis(2-pyridylmethylene)-1,2-(R,S)-cyclohexanediamine ligand was synthesized and characterized by single crystal and powder X-ray diffraction.The crystal lattice of the complex is capable of absorbing and desorbing selectively acetonitrile molecules,at 293 K upon an acetonitrile vapor pressure of^0.1×10^5 Pa.This process,which is partially reversible,can be easily followed by both powder X-ray diffraction(P-XRD)and Eu(III)luminescence spectroscopy.The acetonitrile molecule,located in the outer coordination sphere of the metal ion,does not affect the radiative transition probability of 5 D0 level of Eu(Ⅲ)and also it does not activate further non-radiative channels from this level.On the other hand,this molecule is capable of affecting the energy position and intensities of the crystal field components of the 5 D0→7 F2 transition.The complex in solid form can be considered a promising material for the optical sensing of acetonitrile vapors.展开更多
The whitlockite-like crystal structure of Ca9Lu（PO4）7 when doped with several ions （Yb3＋, EU3＋ and Pr3＋） at different concentrations （1 tool.%, 5 mol.% and 10 tool.%） was studied, by means of synchrotron X-ra...The whitlockite-like crystal structure of Ca9Lu（PO4）7 when doped with several ions （Yb3＋, EU3＋ and Pr3＋） at different concentrations （1 tool.%, 5 mol.% and 10 tool.%） was studied, by means of synchrotron X-ray diffraction. In particular for Eu3＋ and Pr3＋, the presence of the dopant ion significantly changed the occupation factors （OFs） of the Ca2＋ and Lu3＋ cations and gave rise to a distortion of the metal-oxygen polyhedra. The observed structural features clearly showed significant impact of the dopant ion on the crystal structure of the host.展开更多
文摘In this paper, thermoluminescence （TL） properties of rare earth Tb^3＋-doped α-Sr2P2O7 were examined after β-irradiation and photoluminescence （PL） properties of samples were examined for proper excitation. All the samples were synthesized by high-temperature combustion method. The X-ray diffraction （XRD） and Fourier transform infrared （FTIR） spectroscopy characterization confirms the formation of pure α-phase with crystallized in orthorhombic structure of samples. The PL emission spectra of all samples exhibit characteristic green emission peaks of Tb^3＋ where the peak at 545 nm has the highest emission intensity for Tb^3＋ con- centration of 5.0 mol%. The TL glow curves of β-irradiated Tb^3＋-doped α-Sr2P2O7 phosphors were recorded at different heating rates of 2, 4, and 6 K.s^-1. TL curves of all sample exhibit combination of two peaks： peak at 420 K shifts toward higher 525 K remains unaffected temperature, while peak at with the increase in Tb^3＋ concentration as well as fading effect. The activation energy and kinetic parameters of the samples were evaluated using thermoluminescence peak shape method.
文摘The Eu(Ⅲ)nitrate complex of the meso-N,N’-bis(2-pyridylmethylene)-1,2-(R,S)-cyclohexanediamine ligand was synthesized and characterized by single crystal and powder X-ray diffraction.The crystal lattice of the complex is capable of absorbing and desorbing selectively acetonitrile molecules,at 293 K upon an acetonitrile vapor pressure of^0.1×10^5 Pa.This process,which is partially reversible,can be easily followed by both powder X-ray diffraction(P-XRD)and Eu(III)luminescence spectroscopy.The acetonitrile molecule,located in the outer coordination sphere of the metal ion,does not affect the radiative transition probability of 5 D0 level of Eu(Ⅲ)and also it does not activate further non-radiative channels from this level.On the other hand,this molecule is capable of affecting the energy position and intensities of the crystal field components of the 5 D0→7 F2 transition.The complex in solid form can be considered a promising material for the optical sensing of acetonitrile vapors.
文摘The whitlockite-like crystal structure of Ca9Lu（PO4）7 when doped with several ions （Yb3＋, EU3＋ and Pr3＋） at different concentrations （1 tool.%, 5 mol.% and 10 tool.%） was studied, by means of synchrotron X-ray diffraction. In particular for Eu3＋ and Pr3＋, the presence of the dopant ion significantly changed the occupation factors （OFs） of the Ca2＋ and Lu3＋ cations and gave rise to a distortion of the metal-oxygen polyhedra. The observed structural features clearly showed significant impact of the dopant ion on the crystal structure of the host.
