Luminescence is often weakened or quenched at high concentrations, a phenomenon widely known as ‘concentration quenching’. A main cause for the quenching process is mechanistically associated with the ‘formation of aggregates’, which is probably why the concentration quenching effect has frequently been referred to as ‘aggregation-caused quenching’ (ACQ).

In 2001, we discovered an uncommon luminogen system, in which aggregation worked constructively, rather than destructively as in the conventional systems. We found that a series of silole derivatives were non-emissive in dilute solutions but became highly luminescent when their molecules were aggregated in concentrated solutions or cast into solid films. Since the light emission was induced by aggregate formation, we termed the process ‘aggregation-induced emission’ (AIE).

- Aggregation-Induced Emission -
- (AIE) -

Tang’s research group has been working on the development of new polymerization routes from alkyne reactions, and has succeeded in the syntheses of a number of new functional conjugated polymers from acetylenic monomers.

The backbones of the acetylenic polymers are pi-conjugated due to the electronic communications between their electronically unsaturated repeat units. This unique electronic structure has the potential to endow the polymers with novel properties which are very difficult, if not impossible, to access by their congeners of condensation and vinyl polymers with electronic saturation. The prerequisite to realize this attractive potential is to establish versatile processes for synthesizing the polymers.

- Acetylenic Polymers -
- (AP) -