• Anthopoulos, Thomas D.
• Jacoutot, Polina
• Wadsworth, Andrew
• Moser, Maximilian
• Bristow, Helen
• Zhang, Tianyi
• Gasparini, Nicola
• Scaccabarozzi, Alberto D.

Abstract

<jats:title>Abstract</jats:title><jats:p>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<jats:sup>−2</jats:sup> at −2 V and a broadband specific detectivity of 10<jats:sup>12</jats:sup> 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.</jats:p>

Topics

• impedance spectroscopy
• microstructure
• morphology
• polymer
• phase
• power conversion efficiency