Recent Advances and Challenges in Graphene-Based Nanomaterials for Photocatalytic CO₂ Reduction

Abstract

Photocatalytic CO₂ reduction is a viable solar-driven approach to sustainably synthesize fuels and chemicals which provides great potential in response to the urgent threat of increasing atmospheric CO₂. Recently, graphene-based nanomaterials have arisen as extremely compelling platforms due to their large surface area, superior electrical conductivity and tunable electrical properties. This highlighted how new developments in graphene-based photocatalysts as CO₂ reduction including fundamental reaction mechanisms, thermodynamics, kinetics as well as light-induced charge separation. The presentation assessed different forms of grapheme (Graphene Oxide (GO), Reduced Graphene Oxide(rGO), doped graphene and 3D graphene) both with respect to their synthesis, functionality and the role of functionalization including for co-catalysts. Certain aspects of improved charge transport and catalytic activity are presented in the coupling of graphene with metal oxides, semiconductors, metals, carbon nitrides and Z-scheme systems. The review critically evaluates previous findings on the influence of differing synthesis methods on morphology, performance and included mechanistic information from spectroscopic and density functional theory (DFT) based studies. In addition to advances like single-atom catalysis, hybrid systems and machine learning based design, the review also discusses issues of catalyst stability, scalability and environmental issues. In the conclusion, future directions for developing graphene-based systems towards effective, scalable and sustainable CO₂ photoreduction are also provided in the review.