Cellulose-based photo-enhanced persistent room-temperature phosphorescent materials by space stacking effects

Cellulose is environmentally friendly bio-based polymer with a large number of hydroxyl groups in its structure, which can easily form hydrogen bond networks. It has the potential to become excellent persistent room-temperature phosphorescence (pRTP) material through rational design. In this work, we reported a simple and universal strategy to obtain polymer film by connecting aromatic derivatives onto cellulose chains and drying them by hot press process. The emission color of pRTP from blue-green to red can be tuned by benzene or different polycyclic aromatic hydrocarbons as grafted groups, as well as the performance of photo-enhanced pRTP property. Notably, the lifetime of the best-performing film could be enhanced from 282.1 ms to 571.1 ms after irradiation for 1 min at room temperature. All the hot-pressed films were able to withstand Young's modulus up to nearly 18.0 GPa and tensile strength of around 80 MPa. The excellent luminescent and mechanical properties were derived from space stacking effects of the grafted groups and abundant intermolecular hydrogen bonding. These results will provide the effective design strategy for the modulation of smart-response pRTP materials, and expand the application range of cellulose-based materials.

Automated summary

This study presents a simple and universal strategy to obtain polymer film from cellulose chains. By connecting aromatic derivatives onto the chains and drying them through hot press process, the emission color of the film can be tuned. The best-performing film shows a significantly enhanced lifetime after irradiation. Additionally, the hot-pressed films exhibit excellent mechanical and luminescent properties due to the space stacking effects of grafted groups and abundant intermolecular hydrogen bonding.