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Modulating the active sites in atomic level is very meaningful to optimize catalyst performance but still very challenge. Herein, Pt catalysts loaded on different supports (ZSM-5, Al 2 O 3 , ZrO 2 , CeO 2) were sulfate modified by in situ pyrolysis of (NH 4) 2 SO 4 mixed with Pt catalyst. Sulfate remarkably improves these catalyst activities for propane combustion, particularly for the sulfate modified Pt/ZSM-5 catalyst with the highest activity among them. Through controlling the amount of (NH 4) 2 SO 4 used and the loading of Pt, Pt/S atomic ratio in the sulfate modified Pt/ZSM-5 catalyst was successfully regulated. Pt/S atomic ratio significantly affects the electron transfer from Pt species to sulfate and also their interaction strength, which is decisive to the synergetic catalysis of sulfate and Pt species. The 5S-2Pt/ZSM-5 with Pt/S atomic ratio of 0.5 shows a moderate strength of sulfate and Pt species interaction, which is responsible for its highest reaction rate of 86.5 μmol·g Pt −1·s−1 at 200 °C. [Display omitted] • Pt based catalysts were modified with sulfate species by in situ pyrolysis of (NH 4) 2 SO 4. • Pt/S atomic ratio was successfully regulated to optimize catalytic activity for propane oxidation. • The synergy catalysis of sulfate and Pt species for propane oxidation is affected by their interaction strength. • Moderately strong interaction between sulfate and Pt species achieves the highest activity. [ABSTRACT FROM AUTHOR]

H 2 O poisoning of platinum-based catalysts for VOCs oxidation is a long-standing problem due to H 2 O strongly competitive adsorption on active sites. In this work, it is found that the H 2 O competitive adsorption on Pt active sites is effectively weakened by enhancing strong metal-support interaction (SMSI) in Pt-based catalyst. SMSI between WO 3 and Pt species occurs in the WO 3 supported Pt catalyst (Pt/WO 3) but disappears in Pt-3W/ZrO 2 due to monolayer dispersed WO 3 on ZrO 2. The formation of aggregated WO 3 species in Pt-3W/SO 4 2--ZrO 2 leads to the SMSI which is further enhanced by SO 4 2--ZrO 2. The enhanced SMSI plays critical role on weakening water vapor adsorption on active sites, thus Pt-3W/SO 4 2--ZrO 2 exhibits both highest activity (T 90 = 200 °C) and water tolerance which is much superior than Pt/ZrO 2 , Pt/WO 3 , Pt-3W/ZrO 2 and Pt/SO 4 2--ZrO 2 under wet condition (5% H 2 O). Our primary results provide a promising strategy for designing superior platinum catalysts for VOCs complete oxidation. [Display omitted] • Pt-based catalyst with high water tolerance was designed by modulating strong metal-support interaction (SMSI). • WO 3 is monolayer dispersed in Pt-3 W/ZrO 2 but aggregates in Pt-3 W/SO 4 2--ZrO 2. • SMSI disappears in Pt-3 W/ZrO 2 catalyst due to monolayer dispersed WO 3. • Aggregated WO 3 leads to SMSI which is further enhanced by SO 4 2--ZrO 2 in Pt-3 W/SO 4 2--ZrO 2. • Enhanced SMSI weakens the adsorption of water steam on active sites thus improves water tolerance of catalyst. [ABSTRACT FROM AUTHOR]