CO₂ Conversion in Cu-Pd Based Disordered Network Metamaterials with Ultrasmall Mode Volumes

Area of Science:

• Plasmonics
• Metamaterials
• Catalysis

Background:

• Plasmons can drive chemical reactions via intramolecular transitions.
• Achieving strong plasmon-molecule coupling requires ultrasmall mode volumes, which is a significant challenge.

Purpose of the Study:

• To introduce copper-palladium (Cu-Pd) plasmonic network metamaterials as scalable platforms for plasmon-assisted catalysis.
• To investigate the catalytic performance and tunability of these novel metamaterials.

Main Methods:

• Fabrication of Cu-Pd plasmonic network metamaterials.
• Characterization of plasmonic properties, including local density of optical states and hotspots.
• Testing catalytic performance in CO2 conversion under light illumination.

Main Results:

• The Cu-Pd networks exhibit unique plasmonic environments with a high density of hotspots, localizing light in mode volumes < 8 × 10^-24 m³.
• Catalytic tests for CO2 conversion showed production rates up to 4.3 × 10^2 mmol g^-1 h^-1.
• Altered reaction selectivity was observed under illumination, and this selectivity could be tuned by altering the network's chemical composition.

Conclusions:

• Cu-Pd plasmonic network metamaterials offer a scalable and effective platform for plasmon-assisted catalysis.
• The ability to tune reaction selectivity by modifying chemical composition provides a versatile approach for optimizing catalytic processes.