The　dopant　WO3　of　the　catalyst　Pt-0.5P&W/TiO2　enhanced　the　SO2　resistance　of　the　catalyst　for　CO　oxidation　in　sintering　waste　gas,　but　it　also　had　an　impact　on　strong　metal-support　interactions　(SMSI),　which　decreased　the　CO　catalytic　activity.　Adding　alkali　metal　Na　to　Pt-0.5P&W/TiO2　can　effectively　improve　the　CO　catalytic　performance.　The　Pt–O–Na　bond　replaced　the　Pt–O–Ti　bond,　allowing　Na　to　act　as　an　electron　and　structure　promoter　instead　of　TiO2　to　contribute　the　electronic　and　synergistic　effects　in　catalysis.　XPS　and　EPR　date　indicated　that　the　positively　charged　group　centered　on　Pt　adsorbed　hydroxyl　groups　by　electrostatic　interaction,　which　co-acted　with　Na　to　form　Pt-Ox(OH)yNa.　In　situ　infrared　data　indicated　that　Na　promoted　the　electron　density　on　the　Pt　surface　leading　to　the　disproportionation　of　CO　on　the　Pt　surface　to　produce　inactive　C*.　The　production　of　C*　facilitated　the　adsorption　and　activation　of　O2　by　blocking　the　single-layer　adsorption　of　CO　on　Pt.　The　active　oxygen　species　adsorbed　on　the　catalyst　surface　increased　the　CO　activity　of　the　catalyst.　In　sulfur-containing　flue　gas　conditions,　SO2　reacted　with　Na　around　Pt　to　generate　sodium　sulfate,　which　enhanced　the　local　acidity　of　the　active　site　and　the　sulfur　resistance　of　the　catalyst.　©　2024　Elsevier　Ltd