Highly Efficient Pyro-Phototronic Effect-Assisted Spectrum-Selective Colloidal Quantum Dot-Based Self-Powered Photodetector

Abstract

This article presents a highly efficient pyro-phototronic effect-assisted filter-free spectrum-selective colloidal quantum dots (CQDs)-based self-powered photodetector. The reported work shows an enhanced pyro-phototronic effect and a selective response for full-width at half-maximum (FWHM) of 57 nm centered around 398 nm. The device exhibits the maximum external quantum efficiency (EQE) of 3.82% at ~400 nm under self-bias conditions, much higher than the previously reported works. The device structure consists of indium-tin oxide (ITO)-coated glass substrate/ZnO QDs/CdSe QDs/MoOx/Au, where ZnO QDs and MoOx act as charge transport layers. The device is illuminated from the backside (substrate side) to achieve the 100% illumination area. The effective pyroelectric coefficient of the device is also found to be 16.83 times higher than other works at a minimal temperature variation of 0.5 K. The device shows the maximum sensitivity <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${(}{I}_{\text {ph}}/{I}_{d}{)}$ </tex-math></inline-formula> of ~330 under the self-bias condition, indicating the device’s suitability for the self-powered photodetector.