Flexible infrared photodetector based on polyethylene terephthalate (PET) supported lead sulfide thin film

Flexible photodetectors are thought to have uses in optoelectronics, biological imaging, and smart wearable systems. The goal of this work was to develop a simple and low-cost method for fabricating a flexible infrared photodetector based on a lead sulfide (PbS) thin film produced on a PET substrate utilizing a simple lowtemperature spray pyrolysis technique. The device has a highest sensitivity to infrared light (562%), a high responsivity (1.06 mA/W), and a short response time (1 ms) at an intensity of 1.72 mW/cm2. During 100 bending tests at a 40 degrees angle, the performance of this flexible devices showed no signs of significant deterioration. The device exhibits a good, reproducible, and steady photoresponse even after bending (under tensile strain). This implies that this Ag/PbS-PET/Ag photodetector will find uses in wearable technology that require the detection of infrared radiation.