Pt-Embedded-Co3O4 hollow structure as a highly efficient catalyst for toluene combustion

Pt embedded Co3O4 hollow structure nanocomposites (Pt@Co3O4) were prepared using a facile metal-organic frameworks (MOFs) sacrificial strategy. The encapsulated Pt catalyst demonstrated an excellent performance for toluene combustion in comparison with a Pt catalyst that was located outside of Co3O4 (Pt/Co3O4) and a bare Co3O4 catalyst. The superior performance can be ascribed to the interaction between Pt and Co3O4, along with the Pt being present in the lower oxidation state, the low-temperature reducibility and the rich surface-active oxygen species. The Pt embedded Co3O4 hollow structure has a greater number of available oxygen vacancies, which boosts the mobility of the active oxygen species. A possible reaction pathway was also proposed based on in situ diffusion reflectance infrared Fourier transform spectroscopy (DRIFTS) spectra, and it was found that the chemically adsorbed toluene was oxidized to surface intermediates (benzyl alcohol, benzaldehyde and benzoate), and finally completely oxidized into CO2 and H2O. This study provides an effective strategy for the design of an advanced embedded catalyst.

Automated summary

The Pt embedded Co3O4 hollow structure nanocomposites (Pt@Co3O4) exhibited superior performance in toluene combustion due to the interaction between Pt and Co3O4, Pt being present in the lower oxidation state, and the high mobility of active oxygen species enabled by a greater number of available oxygen vacancies in the structure. The study also proposed a possible reaction pathway based on in situ DRIFTS spectra, showing that chemically adsorbed toluene was oxidized to surface intermediates and eventually completely oxidized into CO2 and H2O.