Thermal-Induced Dynamic Self-Assembly of Adenine-Grafted Polyoxometalate Complexes.
作者:?Zhenfeng He, Yi Yan, Bao Li, Huanbing Wang, Hui Ai, Haolong Li,* Lixin Wu,
关键字:organic-inorganic hybrid complex,dynamic self-assembly,polyoxometalate
论文来源:期刊
具体来源:Dalton Trans, 2012, 41, 10043–10051.
发表时间:2012年
A new kind of organic–inorganic hybrid complexes based on polyoxometalate were synthesized through
symmetrically grafting two adeninyl groups onto Anderson-type MnMo6 clusters and encapsulating the
clusters by organic surfactants. The resultant complexes exhibited thermal-induced dynamic self-assembly
behaviors which greatly depended on the ambient temperature and the chain length of cationic
surfactants. With the encapsulation of a short surfactant tetrabutyl ammonium, the complex assembled
into fibrous, rod-like, and tubular architectures respectively upon heating; while for the case of using a
long surfactant dimethyldioctadecyl ammonium as counter ions, the assemblies of the complex
transformed from fibers to spheres with the increased temperature. Moreover, the two types of
transformations were both reversible during a cooling process. The related mechanism was investigated by
combining multiple characterization methods including X-ray crystallography, XPS, FT-IR and
temperature-dependent 1H NMR, which indicated that such a thermal-induced morphological
transformation resulted from a synergy effect of the variation of the multiple hydrogen bonds among the
complexes and the rearrangement of the surfactants surrounding the MnMo6 clusters. These results
demonstrated a new concept that hydrogen bonds can be rationally employed as the driving force for the
fabrication of polyoxometalate-based materials with smart responsive properties.