Achieving visible-light-excited organic room-temperature phosphorescence by manipulating p-pi conjugation

The development of organic room-temperature phosphorescence (RTP) materials has been a rich research field. However, there are still limited practical and directive strategies to regulate the phosphorescence emission. Herein, six naphthalene-based thiochromanone analogs with different heterocycles were synthesized. And all these molecules exhibited bright phosphorescence when embedded into a polyvinyl alcohol matrix under ambient conditions. The absorption spectra showed a distinct red-shift as the size of the heterocycle shrunk, which resulted from the facilitated p-pi conjugation. In particular, the absorption spectra of molecules with a five-membered heterocycle were extended to visible light, which is rarely reported for RTP materials. These results might present a new strategy to adjust the photophysical properties of phosphors to obtain phosphorescence materials with the desired excitation and emission wavelength.

Automated summary

Six naphthalene-based thiochromanone analogs with different heterocycles were synthesized, showing bright phosphorescence when embedded into a polyvinyl alcohol matrix. The absorption spectra red-shifted as the size of the heterocycle decreased, with molecules containing a five-membered heterocycle extending to visible light, offering a new strategy for adjusting photophysical properties of phosphors.