Microporous metal - Organic frameworks formed in a stepwise manner from luminescent building blocks
Microporous metal - Organic frameworks formed in a stepwise manner from luminescent building blocks
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DOI：
10.1021/ja060666e
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发表时间：
2006-08-16
影响因子：
15
通讯作者：
Shimizu, George K. H.
中科院分区：
文献类型：
--
作者：
Chandler, Brett D.;Cramb, David T.;Shimizu, George K. H.
一系列三价稀土元素(Sm、Eu、Gd、Tb、Dy)与二阴离子配体4，4‘-二磺酸-2，2’-联吡啶-N，N‘-二氧化物L以3：1的比例配位，形成三阴离子配合物。然后通过添加BaCl2将这些单元交联成网络固体，以形成式为{Ba-2(H2O)(4)[LnL(3)(H2O)(2)](H2O)(n)Cl}(infinity)，Ln=Sm3+(1)、Eu3+(2)、Gd3+(3)、Tb3+(4)、Dy3+(5)的混合金属网络。这些网络是等结构的，含有开放的通道，很容易吸收和释放水分，伴随着海绵状的收缩和宿主的膨胀。CO2吸附测试证实了微孔率，其DR表面积为718m(2)/gm，平均孔径为6.4埃。配体L敏化了除Gd3+外的所有稀土离子。通过对一系列Ln络合物的研究，可以确定L的三重态能量，它本身就是一种用于敏化目的的新配体。在多孔网络固体中保持了稀土构筑块的发光性能。根据发光数据，可以将该网络的海绵状性质归因于Ba2+配位球而不是Ln(3+)中心。用X-射线结晶学、X射线衍射仪、DSC/TGA、水蒸气和气体吸附、发光光谱等手段对网络进行了表征。
A series of trivalent lanthanides (Sm, Eu, Gd, Tb, Dy) have been complexed to the dianionic ligand, 4,4'-disulfo-2,2'-bipyridine-N,N'-dioxide, L, in a 3:1 ratio to form trianionic complex building blocks. These units were then cross-linked into a network solid by addition of BaCl2 to form mixed-metal networks of formula {Ba-2(H2O)(4)[LnL(3)(H2O)(2)](H2O)(n)Cl}(infinity), Ln = Sm3+ (1), Eu3+ (2), Gd3+ (3), Tb3+ (4), Dy3+ (5). The networks were isostructural and contained open channels which readily absorbed and desorbed water accompanied by a spongelike shrinkage and expansion of the host. CO2 sorption measurements confirmed microporosity giving a DR surface area of 718 m(2)/gm and an average pore size of 6.4 angstrom. Ligand L sensitized all the lanthanide ions with the exception of Gd3+. Studying the series of Ln complexes allowed the determination of the triplet state energy of L which is itself a new ligand for sensitization purposes. The luminescent properties of the lanthanide building blocks were retained in the porous network solid. From the luminescence data, it was possible to attribute the spongelike properties of the network to the Ba2+ coordination sphere rather than the Ln(3+) center. Networks were characterized by X-ray crystallography, PXRD, DSC/TGA, water vapor and gas sorption, and luminescence spectroscopy.