A photothermal MXene-derived heterojunction for boosted CO₂ reduction and tunable CH₄ selectivity

Area of Science:

• Materials Science
• Photocatalysis
• Green Chemistry

Background:

• Efficient conversion of carbon dioxide (CO2) into valuable products is crucial for sustainable energy and environmental remediation.
• Developing advanced photocatalysts with enhanced activity and selectivity is a key challenge in CO2 reduction.

Purpose of the Study:

• To develop a novel Bi2WO6/Ti3C2Tx@Ag (BT@Ag) composite photocatalyst for efficient CO2 reduction.
• To investigate the role of Ti3C2Tx MXene and Ag nanoparticles in enhancing photocatalytic activity and CH4 selectivity.
• To understand the underlying mechanisms of photothermal conversion and surface plasmon resonance in the catalytic process.

Main Methods:

• Synthesis of Bi2WO6/Ti3C2Tx@Ag (BT@Ag) composite photocatalyst.
• Characterization of the material using various analytical techniques.
• Photocatalytic CO2 reduction experiments under simulated solar light irradiation.
• Density functional theory (DFT) calculations to elucidate reaction mechanisms.

Main Results:

• The BT@Ag composite exhibited efficient CO2 reduction to CH4 with tunable selectivity.
• Ti3C2Tx MXene facilitated charge carrier separation and provided active sites for CO2 adsorption and reduction.
• In situ deposited Ag nanoparticles enhanced hot electron generation via surface plasmon resonance, further boosting CH4 production.
• DFT calculations confirmed the crucial role of Ti3C2Tx in CO2 reduction and CH4 selectivity.

Conclusions:

• The developed BT@Ag photocatalyst demonstrates significant potential for efficient and selective CO2 conversion.
• The synergistic effects of photothermal conversion, MXene heterointerfaces, and plasmonic Ag nanoparticles are key to the enhanced performance.
• This work offers a promising strategy for designing advanced photocatalysts for sustainable chemical synthesis.