MXene-based materials for light-driven and light-assisted CO2 conversion processes: Photocatalytic, photoelectrocatalytic, and photothermal approaches.

The swift rise in atmospheric CO2 has intensified the demand for catalytic systems capable of converting this thermodynamically stable molecule into lucrative fuels using renewable energy sources. MXenes, an emerging category of Two-dimensional transition metal carbides, nitrides, and carbonitrides, have become promising candidates for light-driven CO2 reduction owing to their metallic conductivity, tunable surface terminations, varied defect chemistry, and significant light-matter interactions. This review offers a mechanism-oriented and thorough perspective on MXene-enabled CO2 conversion under various light-driven situations, including photocatalytic, electrocatalytic, photoelectrocatalytic, and photothermal processes. We systematically associate synthesis strategies, structural evolution, surface chemistry, and nanoarchitectural design with catalytic performance, emphasizing the diverse functions of MXenes as dynamic electron reservoirs, interfacial charge mediators, plasmonic photothermal transducers, and chemically active sites for CO2 adsorption and activation. Significant focus is directed towards heterojunction engineering, quantum dot integration, and Light-assisted CO2 conversion pathways effects that collectively diminish charge recombination, lower reaction barriers, and enhance product selectivity. This review simultaneously assesses stability, toxicity, and environmental sustainability-domains that have been insufficiently explored in prior MXene research. In addition to CO2 conversion, the multifunctionality of MXenes in energy storage, wastewater treatment, and pollutant elimination is succinctly emphasized to underscore their wider significance for sustainability.