Plasmonic Photocatalysis of Nitrous Oxide into N and O Using Aluminum-Iridium Antenna-Reactor Nanoparticles.

Photocatalysis with optically active "plasmonic" nanoparticles is a growing field in heterogeneous catalysis, with the potential for substantially increasing efficiencies and selectivities of chemical reactions. Here, the decomposition of nitrous oxide (NO), a potent anthropogenic greenhouse gas, on illuminated aluminum-iridium (Al-Ir) antenna-reactor plasmonic photocatalysts is reported. Under resonant illumination conditions, N and O are the only observable decomposition products, avoiding the problematic generation of NO species observed using other approaches. Because no appreciable change to the apparent activation energy was observed under illumination, the primary reaction enhancement mechanism for Al-Ir is likely due to photothermal heating rather than plasmon-induced hot-carrier contributions. This light-based approach can induce autocatalysis for rapid NO conversion, a process with highly promising potential for applications in NO abatement technologies, satellite propulsion, or emergency life-support systems in space stations and submarines.