Discovery of a Robust Single-Atom Ruthenium Emission Control Catalyst

Herein, we discover a robust emission control catalyst featuring Ru single-atom sites even undergoing thermal oxidative aging at 850°C in a 10%H₂O/10%O₂/N₂ mixture gas stream, expecting to substitute the traditional Rh catalysts by cutting ∼73% of the total cost. The stability challenges in elevated-temperature oxidizing environments were overcome via constructing the isolated Ru atoms anchored by square-planar coordination with four lattice oxygen in ceria and suppressing Ru atom migration toward the single Ru─O_x─Ce catalytic centers by introducing the Zr-rich materials, which are conducive to inhibiting the formation of undesirable N₂O by-products during catalytic NO reduction. More importantly, the challenge of low-temperature C─H bond activation in short-chain alkanes on the isolated single-atom sites was broken through by constructing the CeZrO-Ru_SA-CeO₂ three-phase interfaces to promote the H-spillover. The low-cost Ru_SA-CeO₂/CZ single-atom catalyst exhibited much better stability, lower selectivity of N₂O and NH₃ by-products, and higher activity for CO conversion under oxygen-lean conditions compared to commercial Rh catalysts for automotive emission control applications. This work opens new avenues for developing the new generation of low-cost, robust emission control catalysts in the future.