Lead Sulphide Colloidal Quantum Dots for Sensing Applications

Colloidal Quantum Dots (CQD) have been widely studied for their peculiar optical characteristics such as enhanced optical absorption and tunable absorption spectrum. Many different photodetectors have been proposed but overall performance is still poor from the point of view of the bandwidth and noise performance. Here we propose the employment of a PbS QD photoconductor as an ultra-high sensitivity fire detector, exploiting the outstanding device responsivity at low optical powers. Moreover, we demonstrate the outstanding flexibility of CQD based devices, employing our detectors also as simple pollution gas sensors for NO2 detection.