Low-temperature catalytic oxidation of toluene using CeO₂@MIL-101(Fe): Stability against water and SO₂

Toluene, a volatile organic compound (VOC), poses significant environmental and health risks, necessitating efficient abatement technologies. This study explores the catalytic oxidation of toluene using CeO₂-supported MIL-101(Fe) metal-organic frameworks (MOFs). A series of CeO₂@MIL-101(Fe) catalysts with varying Ce loadings were synthesized and characterized through XRD, BET, XPS, SEM-EDS, HRTEM, H₂-TPR, and in situ DRIFTS analyses. Among the synthesized materials, 6 % CeO₂@MIL-101(Fe) exhibited superior catalytic performance, achieving 90 % toluene conversion (T₉₀) at 239 °C, alongside remarkable stability over 60 hours. The catalyst demonstrated high tolerance to water vapor and sulfur dioxide (SO₂), with full activity recovery after inhibitor removal. In situ DRIFTS and PTR-MS provided insights into the reaction mechanism, indicating that lattice oxygen plays a crucial role in toluene activation. The synergistic interaction between CeO₂ and MIL-101(Fe) enhances redox properties and oxygen mobility, improving catalytic efficiency. These findings offer valuable insights into designing robust, MOF-based catalysts for VOC removal, providing a promising approach to mitigating air pollution.