Dual Fluorescence Enhanced Photorecovery Behavior of OFET Memories Based on Carbazole‐Based Polymer Electrets

Comprehensive Summary Recent advances in photoresponsive OFET memories have demonstrated the significant benefits of incorporating optical bias as a fourth terminal control. Herein, three novel carbazole‐based polymers are designed and synthesized via Friedel‐Crafts polymerization. The polymers serve as photoresponsive electrets, where carbazole moieties act as charge‐trapping sites and photoactive units. The penta‐cene‐based OFET memory device incorporating solution‐processed PAnCz exhibits a large memory window (54.4 V), fast programming speed (<20 ms), high hole‐trapping density (4.61 × 10 12 cm –2 ) and reliable charge retention. PAnCz and PDPhCz devices demonstrate significantly improved photorecovery efficiency compared to that of PDFlCz. The superior performance is attributed to their dual fluo‐rescence emission under 350 nm (0.6 mW/cm 2 ) light illumination. The dual fluorescence phenomenon facilitates efficient generation, separation and recombination of photocarriers, which consequently improves the photomodulation efficiency of the devices. This study suggests that dual‐fluorescent polycarbazole electrets represent a promising materials platform for photoresponsive OFET memory.