Montmorillonite-derived porous TiO 2 /SiO 2 supported Pt catalysts for efficient toluene oxidation: synergistic effect and electronic interaction

The reduction of volatile organic compounds (VOCs), especially the oxidation of highly toxic and chemically resistant toluene, remains a challenge in environmental catalysis.In this research, a porous TiO 2 /SiO 2 support was initially fabricated through titanium pillaring of montmorillonite and then calcined and acid-leached as an efficient platform for Pt nanoparticle immobilization to yield Pt-TiO 2 /SiO 2 .The experimental data showed that the catalyst loaded with 0.37 wt.% Pt (0.37Pt-TiO 2 /SiO 2 ) exhibits superior toluene oxidation performance, reaching a T 90 of 190C.Moreover, the catalyst exhibited remarkable water resistance, maintaining high efficiency even in the presence of 10% water vapor and outstanding long-term stability, with no substantial deactivation after 48-h of continuous operation.The performance improvement is explained by the high dispersion of Pt nanoparticles on the support and the metal-support interaction between Pt and TiO 2 , characterized by electron transfer from TiO 2 to Pt.This interaction facilitates the adsorption and activation of reactant molecules.In situ DRIFTS explained the catalytic mechanism: toluene is sequentially transformed into benzyl alcohol, benzaldehyde, and benzoate intermediates, which are subsequently converted to maleic anhydride by opening the ring and eventually mineralized into CO 2 and H 2 O.This work developed a high-performance, durable catalyst, using cost-effective and abundant natural minerals, offering promising prospects for practical abatement of industrial VOCs.