Solution-processed high-performance colloidal quantum dot tandem photodetectors on flexible substrates

We report a high-performance colloidal quantum dot (CQD)-based near-infrared tandem photodetector fabricated on flexible substrates via solution-processed method. The tandem photodetector on poly(ethylene terephthalate) substrates exhibited low dark current and high detectivities over ∼8.8×10¹¹ Jones at near infrared range at -0.5V bias and over ∼10¹³ Jones near 0 bias. The critical bend radii of ∼8mm and ∼3mm have been demonstrated for tensile and compressive bending, respectively. The performance of photodetectors remains stable under mechanical stress, making PbSe CQD material a promise candidate for flexible infrared sensing applications.