A novel fluorescent sensor for Al^(3+)and Zn^(2+)based on a new europium complex with a 1,10-phenanthroline ligand

A new europium complex Eu(tta)_(3)Li(la)based on 1,10-phenanthroline derivative(Li=(2-(3,5-dimethoxyphenyl)-1 H-imidazo[4,5-f][1,10]phenanthroline),tta=2-thenoyItrifluoroacetone)was designed and synthesized.Its structure was characterized by^(1)H and^(13)C NMR,elemental analysis,UV-vis,fluorescence spectra and single crystal X-ray diffraction.The crystal of the complex la belongs to monoclinic system with the space group P2_(1/n).The europium complex la in the solid and in the solution displays the typical emission of Eu(III)ion centered at 612 nm as a result of the electric dipole transition(^(5)D_(0)-►^(7)F_(2)).It exhibits high quantum yield(20.42%),long lifetime(0.29 ms)and good CIE color coordinate(0.67,0.33)in solid.In addition,the complex shows high sensitivity and selectivity towards Al^(3+)and Zn^(2+)in methanol solution which can be attributed to the Al^(3+)/Zn^(2+)cation instead of Eu^(3+)in the complex la.The LODs for Al^(3+)and Zn^(2+)were calculated to be 5.880×10^(-7)and 7.678×10^(-8)mol/L,respectively.Besides,the additions of Al^(3+)and Zn^(2+)express remarkable color changes from red to bright blue and ivory that can be clearly observed by the naked eye respectively.

Stepwise construction of Pt decorated oxygen-deficient mesoporous titania microspheres with core-shell structure and magnetic separability for efficient visible-light photocatalysis

Solid photocatalysts with high specific surface area,superior photoactivity and ease of recycling are highly desired in chemical process,water treatment and so on.In this study,a facile stepwise sol-gel coating approach was utilized to synthesize Pt decorated oxygen-deficient mesoporous titania microspheres with core-shell structure and convenient magnetic separability(denoted as Fe3 O4@-SiO2@Pt/mTiO2-x).These photocatalysts consist of magnetic Fe3 O4 cores,nonporous insulating SiO2 middle layer and mesoporous anatase TiO2-x shell decorated by Pt nanoparticles(~3.5 nm)through wet impregnation and H2 reduction.As a result of high activity of oxygen-deficiency of black TiO2-x by H2 reduction and efficient inhibition of electron-hole recombination by Pt nanoparticles,the rationally designed core-shell Fe3 O4@SiO2@Pt/mTiO2-x photocatalysts exhibit superior photocatalytic performance in rhodamine B(RhB)degradation under visible light irradiation,with more than 98%of RhB degraded within 50 min.These core-shell structured photocatalysts show excellent recyclability under the assistance of magnetic separation with well-retained photocatalytic performance even after running five cycles.This stepwise synthesis method paves the way for the rational design of a high-efficiency recyclable heterogeneous catalyst,including photocatalysts,for various applications.