Afterglow Performance of Phenylenevinylene-Based Semiconducting Polymer Nanoparticles Doped with Photosensitizers...

It is usually believed that doping with photosensitizers capable of generating singlet oxygen (¹O₂) plays a pivotal role in enhancing the afterglow performance of semiconducting polymer nanoparticles (SPNs). However, the effect of doping photosensitizer bearing electron-withdrawing groups has not been reported. Here we report the effect of doping with six photosensitizers possessing different electron-withdrawing groups on the afterglow performance of SPNs using poly[(9,9-di(2-ethylhexyl)-9H-fluo-rene-2,7-vinylene)-co-(1-methoxy-4-(2-ethylhexyloxy)-2,5-phenylenevinylene)] (PF-MEHPPV) as substrate. It was found that the afterglow performance of SPNs was significantly influenced by doping with photosensitizers bearing electron-withdrawing groups. For the doped photosensitizers with strong electron-withdrawing groups, the stronger the electron-withdrawing ability of the group, the worse of the afterglow performance of the SPN regardless of the ¹O₂ generation ability of the photosensitizer. When the doped photosensitizer exhibited weak or none electron-withdrawing effect, the ¹O₂ generation ability of the photosensitizer played a dominant role on the afterglow performance of the SPNs. This work deepens the understanding of the design and synthesis of SPNs with different afterglow properties.