Integrated manufacturing of REciclable multi-material COmposites for the TRANSport sector
Non?Halogenated Solvent Processed Shortwave Infrared Organic Photodetectors Using Sub?1 eV Bandgap Acceptor with Cyano Substitution
An organic photodetector using a cyano?substituted non?fullerene acceptor (6CN) achieves efficient shortwave infrared (SWIR) detection up to 1250 nm. Processed from the eco?friendly solvent o?xylene, the devices deliver excellent responsivity and low noise.Shortwave infrared (SWIR) organic photodetectors (OPDs) offer significant potential but face persistent challenges such as limited responsivity and high noise under reverse bias. This work presents the development of high?performance OPDs for SWIR sensing, leveraging a newly designed non?fullerene acceptor (NFA) named 6CN. The 6CN molecule, featuring a fused?cyclopentadithiophene (fCPDT) core and cyano?substituted ??bridges, exhibits an ultra?narrow optical bandgap of ?0.98 eV, enabling efficient SWIR absorption up to 1250 nm. When blended with the PTB7?Th polymer donor, the resulting bulk?heterojunction (BHJ) demonstrates strong charge transfer, broad spectral coverage, and robust charge transport. Notably, device fabrication employs the environmentally friendly solvent o?xylene without halogenated additives, yielding OPDs with superior photoresponse compared to those processed from conventional chlorinated solvents. The o?xylene processed devices achieve high responsivity (?0.2 A W?1 at 1200 nm) and specific detectivity exceeding 3 × 1011 Jones across 300–1200 nm, representing a significant advance for eco?friendly, flexible SWIR photodetection technologies.
» Publication Date: 17/11/2025
This project has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement Nº 768737
