The Effect of pH on the Optical Band Gap of PbSe Thin Film with Usability in the Quantum Dot Solar Cell and Photocatalytic Activity

Abstract

This study was an attempt to provide a simple solution processed synthesis route for Lead Selenide (PbSe) nanostructure thin films using the chemical bath deposition (CBD) method which is commercially available in inexpensive precursors. In the CBD method, the preparation parameters play a considerable role and determine the nature of the final product formed. Known as two main factors, the effects of complex agent (PH) and time of reaction to the evolution of the configuration and the optical band gap of PbSe nanostructured with self-assemble arrays were investigated in this study. These preparation parameters were tuned to the effect that the nanostructured semiconductors had the band gaps of around 1.4 eV and they could therefore be used for the quantum dot solar cell. The films were characterized by X-ray diffraction (XRD), UV-visible spectroscopy for energy band gap estimation and scanning electron microscopy (SEM) to morphology investigation as well as size distribution. The change in the pH altered the optical band gap from 3.56 to 1.4 eV. The exceptional photo-catalytic behavior from the increased visible light absorption supported the separation of photo-generated electrons and holes, and it also improved the photo-catalytic oxidizing species with the PbSe nanostructured thin films.