Engineering Ir-O-Ce interfaces and tuning Ir⁰ Facet by anchoring Ir on SiO₂-induced dispersed CeO₂ to boost selective...

Simultaneous elimination of CO and NO_x remains a formidable challenge, largely due to the competitive oxidation reactions present in industrial emission streams. Although much prior research has concentrated on enhancing performance at low temperatures, limited catalytic activity in O₂-containing environments has recently gained attention as a pressing issue. Herein, we developed an Ir/Si₂Ce₁O_x catalyst via a SiO₂-induced structural regulation strategy, which promotes the fine dispersion of CeO₂ and enables the strong anchoring of Ir species. This rational design facilitates the preferential exposure of the active Ir⁰ (111) crystal plane, a key factor associated with optimized surface adsorption behavior. Furthermore, the abundant Ir-O-Ce interfaces in this unique architecture induce significant electron transfer from Ce to Ir, thereby stabilizing the metallic Ir⁰. Concurrently, the activated lattice oxygen at the Ir-O-Ce interfaces facilitates the formation of the key nitrate intermediates. Consequently, the catalyst demonstrates outstanding NO reduction and CO oxidation efficiency at 250 °C under oxygen-containing conditions. Our findings highlight a viable approach for stabilizing Ir⁰ through tailored IrCe interactions, offering a pathway to robust CO-selective catalytic reduction (CO-SCR) performance in an oxidative environment.