Reaction behaviors and kinetics of catalytic oxidation of toluene with different feed flows over Pt/Zr(x)-HMS catalysts with Si/Zr ratio equal to 5, 10, 20 and 35 were investigated over a wide temperature range (200 – 500 oC). Results show that Pt/Zr(x)-HMS performs more easily toluene oxidation. The kinetic data were fitted by the Power-law and Mars–van Krevelen kinetic models. The fitting res...

Whilst the Mars-van Krevelen mechanism is well established for metal oxide catalysed oxidation reactions, it has been much less studied in case of nitrogen based reactions by nitrides. In this overview, some recent literature relation to possible operation Mars- van ammonia synthesis nitrides presented, along with relating via chemical looping approaches.

The selective oxidation of propylene to acrolein was investigated over a well-defined supported V2O5/Nb2O5 catalyst, containing a surface vanadia monolayer, with combined operando Raman/IR/MS, temperature programmed surface reaction (TPSR) spectroscopy and isotopically labeled reactants (O2 and C3D6). The dissociative chemisorption of propylene on the catalyst forms the surface allyl (H2CdCHCH2...

Pt/MoOx/TiO2 shows excellent catalytic performance for the reverse water-gas shift reaction at 250 °C via Mars–van Krevelen mechanism.

The effect of pretreatment conditions on the oxidation state and activity of micelle-synthesized Pt nanoparticles supported on ZrO2 was studied for methanol decomposition and oxidation reactions. An O2-pretreatment is observed to be effective for producing clean, stable, and active nanoparticles. Pt-oxide species formed during such pretreatments were found to have little influence in methanol d...

Dispersion-corrected periodic DFT calculations have been applied to elucidate the Langmuir−Hinshelwood (dissociative) and an Eley− Rideal/Mars−van Krevelen (associative) mechanism for ammonia synthesis over Co3Mo3N surfaces, in the presence of surface defects. Comparison of the two distinct mechanisms clearly suggests that apart from the conventional dissociative mechanism, there is another mec...

DFT+U calculations of CO oxidation by Au12 nanoclusters supported on a stepped-CeO2(111) surface show that lattice oxygen at the step edge oxidizes CO bound to Au NCs by the Mars-van Krevelen (M-vK) mechanism. We found that CO2 desorption determines the rate of CO oxidation, and the vacancy formation energy is a reactivity descriptor for CO oxidation. Our results suggest that the M-vK mechanism...

Oxide-supported transition-metal clusters and nanoparticles have attracted significant attention owing to their important role as components of model catalysts, sensors, solar cells and magnetic recording devices. For small clusters, functionality and structure are closely interrelated. However, knowledge of the structure of the bare cluster is insufficient as the interaction with the chemical ...

The influence of the support material of vanadia catalysts on the reaction rate, activation energies, and defect formation enthalpies was investigated for the oxidative dehydrogenation of ethanol and propane. Characterization by infrared absorption–reflection spectroscopy (IRAS), Raman and UV–vis spectroscopy verifies a high dispersion of vanadia for powder and thin-film model catalysts. The su...