Ternary organic photodetectors based on pseudo-binaries nonfullerene-based acceptors

Journal article

The addition of a third component to a donor:acceptor blend is a powerful tool to enhance the power conversion efficiency of organic solar cells. Featuring a similar operating mechanism, organic photodetectors are also expected to benefit from this approach. Here, we fabricated ternary organic photodetectors, based on a polymer donor and two nonfullerene acceptors, resulting in a low dark current of 0.42 nA cm−2 at −2 V and a broadband specific detectivity of 1012 Jones. We found that exciton recombination in the binary blend is reduced in ternary devices due to the formation of a pseudo-binary microstructure with mixed donor–acceptor phases. With this approach a wide range of intermediate open-circuit voltages is accessible, without sacrificing light-to-current conversion. This results in ternary organic photodetector (TOPD) with improved Responsivity values in the near-infrared. Moreover, morphology analyses reveal that TOPD devices showed improved microstructure ordering and consequentially higher charge carrier mobilities compared to the reference devices

Authors: Zhang, T; Moser, M; Scaccabarozzi, AD; Bristow, H; Jacoutot, P

• Publication status: Published
• Peer review status: Peer reviewed
• Publisher: IOP Publishing
• Journal: JPhys Materials
• Volume: 4
• Issue: 4
• Pages: 045001-045001
• Publication date: 2021-06-16
• DOI: 10.1088/2515-7639/ac0c0a
• EISSN: 2515-7639
• ISSN: 2515-7639
• Language: English
• Keywords: Computer science; Physics; Energy conversion efficiency; Optoelectronics; Responsivity; Materials science; Organic solar cell; Photodetector; Polymer; Ternary operation; Acceptor; Dark current