The luminescent nanosized Eu-MCM （1：10） was synthesized by means of sol-gel-assisted self-assembly under basic conditions at room temperature. The results of ^29Si-MAS NMR show that the peaks are Q^4, Q^3, Q^2[ （...The luminescent nanosized Eu-MCM （1：10） was synthesized by means of sol-gel-assisted self-assembly under basic conditions at room temperature. The results of ^29Si-MAS NMR show that the peaks are Q^4, Q^3, Q^2[ （SiO）4-mSi - （OH）m（m=0, 1, 2）, at -δ111, -δ103, -δ90], and q^3, q^2, q^1, q^0[（SiO）4-nSi-（O-Eu）n（n=1, 2, 3, 4）, at - δ83, - δ72, - δ55, - δ47]. The result proves Eu^3＋ doped Si - O framework. The HRTEM image shows that the regular uniform nanoparticles with a diameter of 15 nm possess large pore with Ф8 nm, which is consistent with the result of N2 adsorption. The patterns of selected-area electron diffraction, XRD, and pore-size distribution plot of Eu-MCM （ 1 ： 10） show that the sample of Eu-MCM （ 1 ： 10） possesses the both of crystal and amorphous phases. The FT IR results indicate that the peaks near 970 cm^-1 are assigned to the deformation vibration of silanol group. The as-product was calcined at 800 ℃ and the mesoporous material possesses enormous specific areas and large pores, which shows that the mesoporous material is ultrastable.展开更多
The rare earth complex Eu(TTA) 3 was successfully encapsulated into MCM 41 mesoporous molecular sieve by the addition of the complex into the sol gel mixture for the synthesis of MCM 41 mesoporous material under m...The rare earth complex Eu(TTA) 3 was successfully encapsulated into MCM 41 mesoporous molecular sieve by the addition of the complex into the sol gel mixture for the synthesis of MCM 41 mesoporous material under microwave radiation. The as synthesized MCM 41 hosted Eu(TTA) 3 mesophase was confirmed to possess hexagonally ordered mesostructure and a uniform crystal size of about 30 nm with XRD and HRTEM techniques. Moreover, the IR spectrum, photoluminescence effect and fluorescence lifetime of the Eu(TTA) 3/MCM 41 hybrid were also studied. An increase in Stokes' shift and no change in luminescence lifetime were observed to the resultant mesophase in comparison with Eu(TTA) 3 in ethanol solution.展开更多
基金Project supported by Appropriative Research Fund for Professor and Doctor , Guangdong Institute of Education (ARF0406)
文摘The luminescent nanosized Eu-MCM （1：10） was synthesized by means of sol-gel-assisted self-assembly under basic conditions at room temperature. The results of ^29Si-MAS NMR show that the peaks are Q^4, Q^3, Q^2[ （SiO）4-mSi - （OH）m（m=0, 1, 2）, at -δ111, -δ103, -δ90], and q^3, q^2, q^1, q^0[（SiO）4-nSi-（O-Eu）n（n=1, 2, 3, 4）, at - δ83, - δ72, - δ55, - δ47]. The result proves Eu^3＋ doped Si - O framework. The HRTEM image shows that the regular uniform nanoparticles with a diameter of 15 nm possess large pore with Ф8 nm, which is consistent with the result of N2 adsorption. The patterns of selected-area electron diffraction, XRD, and pore-size distribution plot of Eu-MCM （ 1 ： 10） show that the sample of Eu-MCM （ 1 ： 10） possesses the both of crystal and amorphous phases. The FT IR results indicate that the peaks near 970 cm^-1 are assigned to the deformation vibration of silanol group. The as-product was calcined at 800 ℃ and the mesoporous material possesses enormous specific areas and large pores, which shows that the mesoporous material is ultrastable.
文摘The rare earth complex Eu(TTA) 3 was successfully encapsulated into MCM 41 mesoporous molecular sieve by the addition of the complex into the sol gel mixture for the synthesis of MCM 41 mesoporous material under microwave radiation. The as synthesized MCM 41 hosted Eu(TTA) 3 mesophase was confirmed to possess hexagonally ordered mesostructure and a uniform crystal size of about 30 nm with XRD and HRTEM techniques. Moreover, the IR spectrum, photoluminescence effect and fluorescence lifetime of the Eu(TTA) 3/MCM 41 hybrid were also studied. An increase in Stokes' shift and no change in luminescence lifetime were observed to the resultant mesophase in comparison with Eu(TTA) 3 in ethanol solution.
