Design, synthesis and properties of a new near-infrared small molecule acceptor for organic photodetector

Abstract

Recently, organic photodetectors (OPDs) have occupied a crucial position in the photoelectric industry due to their low cost and convenient production. For its potential applications in near-infrared (NIR) wavelengths, NIR-OPDs with high responsivity and detectivity have attracted a lot of research interest. In this manuscript, we designed and synthesized a new n-type semiconductor, TPBT-OR, by introducing alkoxythiophene into Y5. TPBT-OR exhibits a small optical bandgap of 1.20 eV and red-shifted absorption peaks of 882 nm in film. Using P3HT as a donor and without much additional treatment in device, broad spectra response over 10 11 Jones (cm Hz 1/2 W −1 ) can be achieved in the wavelength of 320 nm–1000 nm with the maximum responsivity of 0.084 A W −1 and detectivity of 7.87 × 10 11 Jones at around 850 nm. Thus, the new TPBT-OR molecule is a promising non-fullerene acceptor in near-ultraviolet to near-infrared detection. • A new ‘A-π-DAD-π-A’ type non-fullerene semiconductor TPBT-OR has been designed and synthesized. • Compared with Y5, it demonstrates a significantly upshifted E HOMO , a slightly downshifted E LUMO , and thus a low optical bandgap of 1.20 eV. • Organic photodetector based on P3HT:TPBT-OR exhibit panchromatic detection between the wavelength of 320 nm and 1000 nm.