Strategic Design of Non-Fullerene Acceptor for High-Detectivity NIR Organic Photodetectors: Incorporating Asymmetric Donor Motif to Achieve Optimal Morphology and Low Dark Current
발표자
()
초록
내용
Development of non-fullerene acceptors (NFAs) for near-infrared (NIR) organic photodetectors (OPDs) has attracted great interest because of their excellent NIR light absorption properties. We developed NFAs by substituting an electron-donating moiety (branched alkoxy thiophene (BAT)) asymmetrically (YOR1) and symmetrically (YOR2) to the Y6 framework. YOR1 exhibited nanoscale phase separation in a blend film with PTB7-Th. Moreover, substituting the BAT unit effectively extended the absorption wavelengths of YOR1 over 1000 nm by efficient intramolecular charge transfer. Also YOR1-OPD significantly reduced dark current and improved photocurrent, resulting in 1.98×1013 Jones specific detectivity at 950 nm. Finally, we successfully demonstrated the application of YOR1-OPD in highly sensitive photoplethysmography sensors. These results suggest a strategic design for all-in-one NFAs for boosting the overall performance of NIR OPDs targeting 1000 nm light signal.