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.