Visible and Near‐Infrared Imaging with Nonfullerene‐Based Photodetectors

Abstract

The solution‐processed organic photodetectors underpin an emerging technology with inherent implications in the biological sensors and imaging displays. Conventional organic photodiodes, the core element of an organic photodetector, rely mainly on fullerene‐based acceptors, which in combination with high and middle bandgap donors, limit the spectral photosensitivity to the visible range. Even in the case of low bandgap polymers the oscillator strength and thus the extinction coefficient are usually limited in the NIR due to the nature of molecular orbital hybridization. Instead, it is showed that pairing prototypical poly(3‐hexylthiophene) (P3HT) with rhodanine‐benzothiadiazole‐coupled indacenodithiophene (IDTBR), a nonfullerene electron acceptor absorbing beyond 750 nm, as the photoactive material of a simple photodiode results in a highly efficient organic photodetector with a record responsivity of 0.42 A W−1 and external quantum efficiency (EQE) of 69% in the NIR (755 nm). Nonfullerene‐based photodiodes are processed on amorphous silicon active matrix backplanes to realize large area flat panel photodetector imagers able to detect objects under visible and NIR light conditions with an exceptional combination of responsivity, dynamic response and image crosstalk.

Blade coated P3HT:non-fullerene acceptor solar cells: a high-throughput parameter study with a focus on up-scalability

“…24 The broad absorption of the P3HT:O-IDTBR system also made it attractive as a photodetector active layer, being sensitive to light from the visible to the near infrared regions. 25 Additionally, Baran et al showed that introducing a third component, namely O-IDFBR, into the P3HT:O-IDTBR blend increased the PCE up to 7.7%. 26 Interestingly, O-IDTBR also demonstrated great performance when blended with other wide band-gap polymers (PvBDTTAZ and PBDTTT-EFT), exceeding 11% PCE.…”

Organic Photodetectors and their Application in Large Area and Flexible Image Sensors: The Role of Dark Current

“…Reported D * values were calculated using Equation , unless otherwise stated. Interestingly, fullerene derivatives are used as electron acceptors in all work, except for some recent exceptions . This implies that the difference in optical and electrical characteristics reported here are largely due to the different polymers used as donor materials.…”

Visible to Near‐Infrared Photodetection Based on Ternary Organic Heterojunctions

“…For instance, Li et al reported a record power conversion efficiency of 14.62% from a single organic junction, and Meng et al boosted the efficiency further to 17.3% through a 2‐terminal tandem architecture . Organic photodetectors (OPDs) based on the BHJs have also shown remarkable device performance, competing with the commercial silicon photodiodes as an alternative technology for next generation photodetection and imaging . Moreover, OPDs can even outperform silicon photodiodes on some metrics, benefiting from the chemical versatility, tunable absorption spectra, and low‐energy embedded solution‐processing …”