Optical and Photoelectrocatalytic Properties of PbS Loaded Si Based Photocathode

Herein, we report an efficient method to produce lead sulfide PbS nanoparticle-decorated silicon (Si) pyramids arrays on a Si substrate by using pure chemical methods. A n-type nanostructured PbS thin films were prepared by chemical bath deposition onto plat Silicon (Si) and pyramid textured Silicon (SiPYs) which were derived from alkaline etching of Si substrates. The morphological characterizations were carried out by Scanning Electron Microscopy (SEM), while the optical properties were studied using Ultraviolet-Visible Spectroscopy (UV-Vis). The catalytic activity was studied by linear sweap voltammetry (LSV) in dark and under white light irradiation using potentiostat station. Cyclic voltammetry in presence and without purging CO2 was also conducted. The LSV investigations showed the synergy effect between PbS thin films and Si for the rising and transport of the charge carriers. The results showed a higher photocatalytic towards CO2 reduction of PbS/SiPYs compared to Silicon substrate without surface modification and sensitization. The electrode based on PbS/SiPYs/Si could efficiently be used as photocathode for the PEC reduction of CO2 to Methanol.

Automated summary

In this study, we developed an efficient method to produce lead sulfide (PbS) nanoparticle-decorated silicon (Si) pyramids arrays on a Si substrate using pure chemical methods. The synergistic effect between PbS thin films and Si was found to enhance the charge carrier transportation, leading to higher photocatalytic CO2 reduction activity for PbS/SiPYs.