Color-tunable fluorescence, phosphorescence and electroluminescence from single-chromophore polymers

Abstract

Color-tunable fluorescence and phosphorescence have aroused great attention owing to their potential applications in display and lighting. However, achieving both color-tunable singlet fluorescence and triplet phosphorescence emission in single-chromophore polymers is still challenging. Herein, we develop two monomers (2-PTZ-BSe and 3-PTZ-BSe) with benzoselenidiazole at the 2- and 3-positions of phenothiazine (PTZ), and then photopolymerized them with NIPAM to obtain a series of polymers (2-PPTZ-BSe and 3-PPTZ-BSe). The resulting polymers present excitation wavelength, feed ratio and photopolymerization time-dependent color tunable fluorescence. Moreover, excitation wavelength, feed ratio and delay time-dependent phosphorescent emissions with lifetimes of hundreds of milliseconds are achieved for the polymers. By taking advantage of this color-tunable singlet and triplet emission feature, color-tunable and standard white electroluminescence with CIE coordinates of (0.35, 0.34) are obtained using the same chromophore in different polymers.