Rare earth inorganic-organic hybrid compounds based on Keggin-type polyoxometalate {SiW_(12)} with fast-responsive photochromism and switchable luminescence properties  

作　　者：Hong Cui Yanli Yang Xue Bai Xu Han Wensha Zhang Ying Lu Shuxia Liu 

机构地区：[1]Key Laboratory of Polyoxometalate and Reticular Material Chemistry of the Ministry of Education,College of Chemistry,Northeast Normal University,Changchun 130024,China

出　　处：《Journal of Rare Earths》2024年第2期286-292,I0003,共8页稀土学报（英文版）

基　　金：Project supported by the National Natural Science Foundation of China(22172022,21872021,21671033,21901135)。

摘　　要：Four rare earth inorganic-organic hybrid compounds based on Keggin-type polyoxometalate {SiW_(12)}with general formula [{RE(DMF)_(4)(H_(2)O)_4RE(DMF)_(6)}_(2){SiW_(12)O_(40)}_(3)](RE = La(1),Pr(2),Sm(3),Eu(4),DMF=N,N-dimethylformamide) were synthesized by the conventional solution method.Structure analyses indicate that four compounds are isostructural and are all built from three [SiW_(12)O_(40)]^(4-) polyoxoanions and DMF ligands linked by RE^(3+).Compounds 1-4 are extremely sensitive to UV light and present excellent photochromic properties,in which the coloring and fading time of samples are both no more than 2 min,and the reversible coloring-fading process can be repeated for at least 10 cycles with little fatigue,suggesting that compounds 1-4 can be a series of fast-responsive and durable photochromic materials.Moreover,the solid-state photoluminescence spectra of compounds 3(Sm) and 4(Eu)display strong characteristic emissions of rare earth ions based on f-f transitions.Meanwhile,compound4(Eu) has a longer fluorescence lifetime up to 566.74 μs.Notably,co mpounds 3(Sm) and 4(Eu) exhibit the switchable luminescence behavior induced by photochromism,which allows them to be used as potential molecular switches.

关 键 词：Inorganic-organic hybrid Keggin-type polyoxometalates Rare earths PHOTOCHROMISM Photoluminescence 

分 类 号：TB34[一般工业技术—材料科学与工程]