MoS₂–Nanosheets-Based Catalysts for Photocatalytic CO₂ Reduction: A Review

Artificial photosynthesis is a clean and sustainable technique to mitigate the increasing greenhouse CO2 concentrations via simultaneous energy production to meet the ever-growing energy demands. A light-assisted CO2 conversion primarily depends on catalytic materials for the prompt adsorption and conversion of CO2 to solar fuels under ambient conditions. An enormous effort shows the development of new photocatalytic materials, and two-dimensional metal dichalcogenides are promising due to their unique surface structure and their low band gap potentials that allow visible-light photocatalysis. Additionally, their tunable optical characteristics and high stability under a continuous illumination are strongly applied in making advanced photochemical devices in several front-line areas. Among metal dichalcogenides, MoS2 is well-explored in hydrogen evolution, pollutants degradation, and the photoreduction of CO2 to valuable fuels (CH4, CO, CH3OH, HCOOH). Considering the unique advantages of MoS2 nanomaterials in a photocatalytic CO2 reduction, yet a single review is lacking that combines all the aspects of CO2 reduction. This review provides a thorough understanding of the MoS2-based nanomaterials for photocatalytic CO2 reduction reactions (PCO2RR) and inspects the current progress in this domain with an initial description centered on insights of the thermodynamics of the photoassisted conversion process. The second portion acquaints the reader with advances in the MoS2-based nanomaterials in their fabrication and associated techniques for tuning the suitable properties by tailoring approaches, particularly doping, heterostructure formation, and self-modifications adopted to enhance the functionality toward proliferating the conversion and selectivity for PCO2RR. Finally, from the context of both theoretical and experimental investigations, we discuss future opportunities and potential strategies to elevate the structural, optical, and carrier dynamic properties to boost the quantum efficiency of MoS2. This contribution may create an avenue to implement cost-effective novel chalcogenides for solving environmental problems via light-meditated sustainable approach.