Unlocking the carbon dioxide photoreduction potential of graphene-derived catalysts: mechanisms, product selectivity, and challenges

Abstract

The escalating concentration of carbon dioxide (CO₂) in the atmosphere necessitates innovative strategies to address global warming and simultaneously harness its potential as a valuable resource. To offset CO₂ emissions, heterogeneous photocatalysis has emerged as an effective technology to photochemically reduce CO₂ into value-added chemicals using specially designed photocatalysts. However, photocatalysts mediating CO₂ reduction often encounter some intrinsic challenges like low specific surface area, inefficient charge separation, narrow visible light absorption, and inadequate stability. Graphene-based materials are widely regarded as a promising solution to address these limitations, offering an enormous specific surface area, excellent electron mobility, and robust chemical stability, which collectively enhance CO₂ conversion efficiency and ensure durable photocatalyst performance. This review delves into the forefront of visible light assisted photocatalytic reduction of CO₂, with a particular focus on graphene-based photocatalysts. The goal is to uncover sustainable solutions that utilize visible light to catalyze the reduction of CO₂, offering an eco-friendly alternative to fossil fuels, while simultaneously acting as a carbon sink by capturing atmospheric CO₂. This review discusses the constraints and challenges of graphene-based composites, encompassing their synthesis techniques and performance efficacy, and provides an outlook on the various product selectivities during CO₂ photoreduction. A brief overview of the potential products obtained from CO₂ photoreduction, with an insight into their plausible mechanism for the production of solar fuel and value-added chemicals, is provided. This timely review, therefore, aspires to expatiate on the recent advances in CO₂ capture and sequestration using graphene-based heterogeneous photocatalysis.