Two dimensional conjugated polymers (2DCPs) are a new type of semiconductor material system. The unique extended two-dimensional conjugated structure of 2DCPs indicates excellent optoelectronic properties and has great application prospects in the field of organic electronics. However, most of the reported 2DCPs materials have relatively poor optoelectronic properties, and there are few reports on two-dimensional conjugated polymer semiconductors with strong fluorescence properties. The reason for the fluorescence quenching of this type of material is that the tight interlayer π - π stacking in the 2DCPs system causes severe energy dissipation, resulting in its non luminescence or poor fluorescence characteristics.

Dong Huanli, a researcher in the Key Laboratory of the Institute of Mechanical and Solid State of the Chemical Research Institute of the Chinese Academy of Sciences, carried out research around the development of 2DCPs semiconductor materials with excellent photoelectric properties. Recently, Dong Huanli's team proposed a new strategy of using side chain engineering to control the preparation of strong fluorescent 2DCPs semiconductor materials. A study was conducted on the preparation of 2DCPs thin films with excellent fluorescence performance using trimeric indene molecules as excellent fluorescent elements and introducing alkyl side chains of different lengths as interlayer spacing control groups. The films were prepared through dynamic interface Glaser Hay coupling reaction, and the fluorescence quantum yield was as high as 14.6%. The fluorescent 2DCPs thin film material has an ultra long quasi two-dimensional exciton diffusion length with in-plane isotropy, with a maximum value close to 110 nm, indicating the effective expansion of two-dimensional π - conjugated structural features in the 2DCPs thin film and demonstrating potential carrier transport performance. This work provides an effective approach for the synthesis of strong fluorescent semiconductor 2DCPs thin films, and provides tools and means for the research and application of such materials in optoelectronic devices and other fields.

The relevant research results are published in CCS Chemistry. The research work has received support from the National Natural Science Foundation of China, the Ministry of Science and Technology, and the National Center for Molecular Science in Beijing.

Paper link:论文链接