Roadmap on the development of 2D nanomaterials for preparation of efficient photocatalysts

The recent push towards sustainability by countries across the globe has compelled that solar-driven catalytic processes take a cleaner and greener route towards energy conversion technologies, besides reducing cost and increasing efficiency. On the other hand, large specific surface area, increased active sites, and improved charge transfer rate due to the 2D nature of materials like graphene and transition metal di-chalcogenides (TMDCs) have made their application in the conversion of solar energy to value-added fuels a subject of detailed research. The ever-changing global outlook towards photocatalysis has relied more on catalyst diversification than resource heterogeneity, helping this technology prioritize a low-carbon, low-cost model. However, amidst all developments, various aspects of recent material modifications have constantly been overlooked, restricting potential parameters that might be targeted for photocatalytic activity enhancement. In this context, this review article focuses on the recent developments of photocatalytic materials involving graphene, 2D black phosphorus , and TMDCs. This article covers the dynamic evolution of 2D composite-based photocatalysis since the COVID era when national governments and international regulatory organizations significantly increased their financial support for greener technological research. The review has been categorized based on the various photocatalytic applications, especially in hydrogen evolution, carbon dioxide reduction, and organic dye degradation. Research data has also been provided on distinct morphologies and mechanisms that have been reported to intrinsically affect photocatalytic activity and interpreted to have a concrete understanding of their possible practical and commercial application. Finally, certain crucial challenges and the future outlook for 2D material-based photocatalysis have been provided to mitigate the nit-bits of roadblocks these materials face for deployment in commercial applications.