Support effect in oxide catalysis: methanol oxidation on vanadia/ceria

Area of Science:

• Surface science
• Catalysis
• Computational chemistry

Background:

• Vanadia species on ceria are crucial catalysts.
• Understanding methanol dehydrogenation is key for chemical synthesis.

Purpose of the Study:

• Investigate methanol adsorption and formaldehyde dehydrogenation on VO2/CeO2(111).
• Elucidate reaction pathways and the role of ceria.

Main Methods:

• Density Functional Theory (DFT) with PBE+U, HSE, and B3LYP functionals.
• Dispersion-corrected calculations (e.g., HSE+D).

Main Results:

• Highly exothermic methanol adsorption (1.8-1.9 eV).
• Two formaldehyde desorption pathways with redox barriers (1.0 and 1.4 eV).
• Calculated desorption temperatures match experimental observations.

Conclusions:

• Ceria participates directly in the redox process, accommodating electrons.
• Two distinct pathways show cooperativity between methanol, vanadium, and ceria.
• DFT accurately models catalytic processes on supported oxides.