《Efficient Catalytic Combustion of Cyclohexane over PdAg/Fe₂O₃ Catalysts under Low-Temperature Conditions: Establishing the Degradation Mechanism using PTR-TOF-MS and in situ DRIFTS》

Website： https://doi.org/10.1021/acsami.2c14515

Graphical Abstract：

ABSTRACT：

Cyclohexane, a typical volatile organic compound (VOC), poses high risks to the environment and humans. Herein, synthesized PdAg/Fe₂O₃ catalysts exhibited exceptional catalytic performance for cyclohexane combustion at lower temperatures (50% mineralization temperature (T₅₀) of 199 ^oC, 90% mineralization temperature (T₉₀) of 315 ^oC) than Pd/Fe₂O₃ (T₅₀ of 262 ^oC, T₉₀ of 335 ^oC) and Fe₂O₃ (T₅₀ of 305 ^oC, T₉₀ of 360 ^oC). In addition, PdAg/Fe₂O₃ displayed enhanced catalytic performance and stability, due to the low-temperature reducibility and the acidity of PdAg/Fe₂O₃ were enhanced by the PdAg alloy. In situ diffuse reflectance infrared Fourier transform spectroscopy and proton-transfer-reaction time-of-flight mass spectrometry were applied to identify the intermediates formed on the catalyst surface and in the tail gas during oxidation, respectively. Results suggested that loading PdAg onto Fe₂O₃ significantly enhanced the adsorption and activation of oxygen and cyclohexane, oxidative dehydrogenation of cyclohexane to benzene, and catalytic cracking of cyclohexane to olefins at low temperatures. This in-depth study will benefit the design and application of efficient catalysts for the effective combustion of VOCs at low temperatures.