A General Dual-Metal Nanocrystal Dissociation Strategy to Generate Robust High-Temperature-Stable Alumina-Supported Single-Atom Catalysts

Designing new synthesis routes to fabricate highly thermallydurableprecious metal single-atom catalysts (SACs) is challenging in industrialapplications. Herein, a general strategy is presented that startsfrom dual-metal nanocrystals (NCs), using bimetallic NCs as a facilitatorto spontaneously convert a series of noble metals to single atomson aluminum oxide. The metal single atoms are captured by cation defects in situ formed on the surface of the inversespinel (AB(2)O(4)) structure, which process providesnumerous anchoring sites, thus facilitating generation of the isolatedmetal atoms that contributes to the extraordinary thermodynamic stability.The Pd-1/AlCo2O4-Al2O3 shows not only improved low-temperature activity butalso unprecedented (hydro)thermal stability for CO and propane oxidationunder harsh aging conditions. Furthermore, our strategy exhibits asmall scaling-up effect by the simple physical mixing of commercialmetal oxide aggregates with Al2O3. The goodregeneration between oxidative and reductive atmospheres of theseionic palladium species makes this catalyst system of potential interestfor emissions control.