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A novel kind of redissolvable gold nanoparticles was prepared by using a poly(phenylene vinylene)-based hyperbranched conjugated polymer as stabilizing agent. The complexation between the surface gold atoms and the bipyridyl groups at the periphery of the hyperbranched polymer prevents the nanoparticles from aggregation. The surface plasmon band of the nanoparticles is insensitive to surrounding media due to the capping with organic layer. The fluorescence of the surface-attached conjugated macromolecule is significantly quenched by the gold nanocore. Solvent polarity effect suggests the occurrence of a photo-induced electron transfer process from the excited bound fluorophore to the nanocore.

A novel light-emitting alternating copolymer, known as hyperbranched conjugated polymer (HPV), has been designed and synthesized by Wittig reaction, and so have its linear counterparts, including MPV and PPV. FTIR,1H NMR,13C NMR and GPC were combined to characterize these polymers. Their photophysical properties were investigated both in solution and in solid film. Interestingly, almost the same maxima of absorption and emission wavelengths were observed for the solution of HPV and MPV in CH2Cl2 respectively, located at the shorter wavelength region related to PPV. In addition, the absorption peak of HPV film blue shifted while its emission peak red shifted as MPV compared with the case of its CH2Cl2 solution. However, both the absorption and emission spectra of the PPV film showed red shift, which resulted from a special electronic structure.

The photophysical properties of the first crown ether-bearing [60]fulleropyrrolidine (CFP) have been studied. The absorption and fluorescence spectra are hypsochromically shifted by metal ions complexation via intramolecular electron transfer which is confirmed by AMI computation. The third-order optical nonlinearity of CFP is measured by time-resolved degenerate four-wave-mixing experiment. The third-order optical susceptibility χ(3) of CFP is 8.97×10−14 esu. The nonlinear optical temporal response is second-order exponential, the fast process is determined as 120 ps.

The Eu(III) ion, as a luminescent probe, is incorporated into a novel nanotube-contained polyorganosiloxane (POS), which is obtained by coupling of ladderlike polyvinylsilsesquioxane (Vi-T) with tetramethyldisiloxane (H-MM) via hydrosilylation, to form POS-Eu(III) composite. The results from fluorescent study demonstrate that the composite is actually a host-guest clathrate which includes the Eu(III) ions in the tubelike cavity of POS and moreover, the supramolecular clathrate exhibits an obvious energy transfer process which converts the UV light absorbed by POS into the visible light generated from the Eu(III) luminescence. Molecular simulation also gives support to the formation of such a clathrate and thus results in energy transfer process.