Many types of research showed that the polymer matrix full of hydrogen-bonding interaction could restrain the non-radiation relaxation (NR) of the organic dyes effectively, and the efficient NIR organic dyes could be generated by suppressing the NR process of the red fluorescence organic dyes with enough intersystem crossing efficiency. Wherein, the NIR RTP organic dyes with a short lifetime are more beneficial to increase the quantum yield of the NIR RTP because the other potential NR process could neutralize the benefits of the forbidden of the IC to quench the NIR emission. This strategy could decrease the threshold for the construction of organic NIR materials. In order to verify this strategy, bromophenol blue derivatives with red light emission, including bromophenol blue, bromophenol red, and tetrabromophenol blue, were selected to test this hypothesis for the short RTP lifetimes of the organic dyes with heavy atoms. Polyvinyl alcohol (PVA) was chosen as the matrix to provide the rigid microenvironment to suppress the NR of the dyes. The experimental data showed that the bromophenol blue derivatives have moderate NIR RTP emission in the PVA matrix, and the tetrabromophenol blue@PVA films showed the best NIR RTP emission with 3.0% NIR RTP quantum yield and 819 nm wavelength. This study preliminarily demonstrates that it is effective to construct materials with NIR emission by using the red fluorescence organic dyes, which provides an idea for developing more organic materials with efficient NIR emission.

Polymer doping strategy for development of near-infrared metal-free phosphorescence dyes

ACS Spring 2022

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.