Light-driven methane dry reforming with single atomic site antenna-reactor plasmonic photocatalysts

Syngas, an extremely important chemical feedstock composed of carbon monoxide and hydrogen, can be generated through methane (CH₄) dry reforming with CO₂. However, traditional thermocatalytic processes require high temperatures and suffer from coke-induced instability. Here, we report a plasmonic photocatalyst consisting of a Cu nanoparticle ‘antenna’ with single-Ru atomic ‘reactor’ sites on the nanoparticle surface, ideal for low-temperature, light-driven methane dry reforming. This catalyst provides high light energy efficiency when illuminated at room temperature. In contrast to thermocatalysis, long-term stability (50 h) and high selectivity (>99%) were achieved in photocatalysis. We propose that light-excited hot carriers, together with single-atom active sites, cause the observed performance. Quantum mechanical modelling suggests that single-atom doping of Ru on the Cu(111) surface, coupled with excited-state activation, results in a substantial reduction in the barrier for CH₄ activation. This photocatalyst design could be relevant for future energy-efficient industrial processes.