Green-Solvent-Processed High-Performance Broadband Organic Photodetectors

Solution-processedorganic photodetectors with broadband activityhave been demonstrated with an environmentally benign solvent, ortho-xylene (o-xylene), as the processingsolvent. The organic photodetectors employ a wide band gap polymerdonor PBDB-T and a narrow band gap small-molecule non-fullerene acceptorCO1-4F, both dissolvable in o-xylene at a controlledtemperature. The o-xylene-processed devices haveshown external quantum efficiency of up to 70%, surpassing the counterpartprocessed with chlorobenzene. With a well-suppressed dark current,the device can also present a high specific detectivity of over 10(12) Jones at -2 V within practical operation frequenciesand is applicable for photoplethysmography with its fast response.These results further highlight the potential of green-solvent-processedorganic photodetectors as a high-performing alternative to their counterpartsprocessed in toxic chlorinated solvents without compromising the excellentphotosensing performance.

Automated summary

Organic photodetectors processed with environmentally benign solvent o-xylene exhibit broad activity. The devices, using PBDB-T polymer donor and CO1-4F non-fullerene acceptor, are dissolved in o-xylene at controlled temperature. The o-xylene processed devices show an external quantum efficiency up to 70%, surpassing chlorobenzene processed counterparts, and have characteristics of suppressed dark current and high specific detectivity within practical operation frequencies.