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

Plasmons can drive chemical reactions by directly exciting intramolecular transitions. However, strong coupling of plasmons to single molecules remains a challenge as ultrasmall mode volumes are required. In the presented work, we propose Cu-Pd plasmonic network metamaterials as scalable platforms for plasmon-assisted catalysis. Due to the absence of translational symmetry, these networks provide a unique plasmonic environment featuring a large local density of optical states and an unparalleled density of hotspots that effectively localizes light in mode volumes V < 8 × 10^-24 m³. Catalytic performance tests during CO₂ conversion reveal production rates of up to 4.3 × 10² mmol g^-1 h^-1 and altered reaction selectivity under light illumination. Importantly, we show that the selectivity of the catalytic process can be tuned by modifying the network’s chemical composition, offering a versatile approach to optimize reaction pathways.