Low-temperature performance controlled by hydroxyl value in polyethylene glycol enveloping Pt-based catalyst for CO/C3H6/NO oxidation

To decrease the diesel vehicle emission, polymer-assisted platinum-based catalysts having an improvement in the dispersion of platinum were developed. This work investigated the structure and redox properties of platinum nanoparticles assisted by polyethylene glycol (PEG) with different hydroxyl value and supported on SiO2-Al2O3 following carbonization and air roasting treatments. Ultraviolet-visible (UV-vis) spectra, in situ FTIR and structural characterization measurements reveal that PEG400-assisted catalyst presents a great interaction with platinum species, affecting the electronic intensity and dispersion of platinum. Reactivity tests show that PEG400-assisted Pt-based catalysts have a better low-temperature catalytic performance in CO, C3H6 and NO oxidation, decreased by around 10-30 degrees C. It is concluded that the differences in reactivity could be related to the formation and stabilization of platinum species during the preparation.