Advances in MoS2 composites for electrocatalytic energy conversion: Synthesis, applications, and future perspectives in hydrogen, oxygen, nitorgen, and CO2 reactions

Abstract

The significant increase in energy demand and environmental challenges requires sustainable technologies to preserve the climate and minimize CO2 emissions. Electrocatalysis for energy conversion applications, such as hydrogen evolution reaction (HER), oxygen evolution reaction (OER), nitrogen reduction reaction (NRR), and CO2 reduction reactions (CCR), are essential in renewable energy technologies. State-of-the-art catalysts are highly needed to enhance energy conversion efficiencies. Recently, Molybdenum disulfide (MoS2) with its distinguished physiochemical properties has been verified as a potential energy conversion material for catalyzing electrochemical reactions, ensuring excellent performance.Aside from graphene, which is unsuitable in some fields due to its zero-energy bandgap, alternative 2D materials like MoS2 have been developed and investigated. MoS2 nanostructures, with a relatively brief history, are emerging as suitable candidates in several applications, especially in electrocatalysis. Enhancing charge transfer and combining MoS2 with other materials can improve energy and environmental application performance.The excellent electrocatalytic progress of MoS2-based composites has been reported alongside enhanced and tunable properties like rich active edges, high density of structural defects, excellent conductivity, well-defined size dispersion, good electrode contact, favorable exposed crystal facets, and maximized phases. These properties, critical in electrocatalysis, are reviewed herein.We describe different methodologies for preparing MoS2 composite materials, illustrating their advantages and limitations for catalysis applications. We discuss the figure of merit of MoS2 composite nanostructures in electrocatalysis and present the challenges and outlooks for this new material class based on recent developments and potential applications in energy and the environment, suggesting promising research directions for the future