Two indole-based organic dyes were conveniently prepared and well characterized. The triphenylamine or carbazole moieties were bonded to the indole group acting as a potential electron donor, which can tune the HOMO and LUMO levels of the resultant dye, and another triphenylamine or carbazole group was linked to the pyrrole ring on the nitrogen atom, which was expected to suppress the aggregation of the dye in the solid state to some degree. These two dyes were utilized as dye sensitizers in dye-sensitized solar cells and demonstrated efficient photon-to-electron conversion properties.

In this paper, two new series of main-chain and side-chain second-order nonlinear optical (NLO) polyurethanes have been successfully prepared, in which isolation groups with different sizes were introduced to adjust the NLO property of the resultant polymers, according to the concept of "suitable isolation groups". The second harmonic generation (SHG) experiments demonstrated that all the polymers exhibited large second harmonic generation (SHG) coefficients of d33 values (up to 105.6 pm/V) with excellent thermal stability and filmforming ability, indicating that the introduction of isolation groups could alleviate the "nonlinearity-stability trade off" efficiently. In addition, for both main-chain and side-chain polymers, BOP acted as the suitable isolation group. It was also found that the positive influence of the linked suitable isolation spacer was more obvious in the main-chain polymers, in comparison with those in the side-chain polymers.

A series of new carbazole-based luminophores (1-12) were synthesized and well characterized, which demonstrated aggregation-induced emission enhancement (AIEE) properties. The obtained experimental results demonstrated that the attachment of aromatic rotors to luminophore moieties would lead to the decreased quantum yields (measured in diluted solutions); the more rotors attached, the smaller the quantum yields tested. This further confirmed that the AIEE phenomena were caused by the restriction of the intramolecular vibrational and rotational motions in an indirect manner.

A series of nonlinear optical (NLO) chromophores were successfully prepared, in which pyrrole moieties were the conjugated bridge. In comparison with their analogues containing furan or thiophene groups as the bridge, these chromophores demonstrated similar or enhanced NLO effects (up to 3.3 times) and interesting optical behavior. While the acceptor groups were malononitrile (Mal), 3-phenyl-5-isoxazolone (Iso), and 1,3-diethylthiobarbituric acid (Bar), the chromophores exhibited much blue-shifted maximum absorption wavelengths (ìmax) (up to 36 nm); however, the ìmax of the chromophore containing tricyanovinyldihydrofuran (TCF) as acceptor became much longer than that of the analogue (up to 75 nm).

Three indole-based nonlinear optical (NLO) chromophores with changeable isolation groups were successfully introduced into the polymer backbone to yield a series of main-chain polyurethanes. Thanks to the mainchain structure and the advantages of the indole-based chromophores, all of the polymers show excellent transparency, good processability, thermal stability, and relatively good NLO effects. The obtained experimental results indicated that the polymer backbone, in addition to the linked isolation moieties, could act as isolation spacers in some special cases. The tested NLO results demonstrated that the isolation groups with apparent site-isolation effect might not benefit the macroscopic NLO effect of the resultant polymers.