Band Edge Engineering in Metal Oxide Heterostructures for Efficient Charge Separation for Solar Water Oxidation in Photoelectrochemical Cell

The conversion of CO2 to useful chemicals and fuels via photocatalytic reaction is a current topic under thorough investigation to solve the environment and energy problem. The main phenomenon that enables CO2 reduction is the bending, upon adsorption to a surface, of the molecule in a partially charged CO2- molecule with a lower LUMO and, therefore, a lower reduction energy. The most challenging part of the CO2 reduction reaction is the selectivity due to the multielectron-transfer process, thus the photocatalysts used in CO2 reduction reaction are of utmost importance. Among the various available photocatalysts or co-catalysts, 2D materials such as MoS2 have shown promising results for photocatalytic reaction of CO2.<br/>In the presentation, we will show our recent work on 2D MoS2-based nanocomposite for photocatalytic reduction of CO2 to chemical fuel. MoS2/MoO3 heterojunction have been prepared by two step synthesis. In first step, 2D MoS2 has been prepared by ultrasonic assisted liquid phase exfoliation of bulk MoS2 in water-IPA (70:30) solution. In second step, the prepared MoS2 nanoflakes were illuminated for different duration using 150 Watts solar simulator for partial oxidation of MoS2 to MoOx. The prepared MoS2/MoO3 heterojunction has been characterized for structural, optical, chemical, electrical, electrochemical properties and finally studied for its application in selective reduction of CO2 to chemical fuel. The obtained results will be discussed in detail during the presentation.