Using a home-built reflectometer, we have investigated the changes in the optical reflectivity of a Pd(100) model catalyst during CO oxidation under high-pressure, high-temperature conditions. We observe changes in optical contrast when exposing the surface to CO oxidation conditions at 200 mbar from room temperature up to 400 °C. These changes in reflectivity are a result both of the formation...

Organic aerosols (OA) can be separated with factor analysis of aerosol mass spectrometer (AMS) data into hydrocarbon-like OA (HOA) and oxygenated OA (OOA). We develop a new method to parameterize H:C of OOA in terms of f43 (ratio of m/z 43, mostly C2H3O, to total signal in the component mass spectrum). Such parameterization allows for the transformation of large database of ambient OOA componen...

The field of complex mixture analysis has advanced significantly in the past two decades, although its history goes much further back. When Dirk Willem van Krevelen developed his now eponymous diagram in 1950 to represent the chemical makeup of coals, he proposed that the chemical nature of samples, including the presence of structural motifs and chemical properties, could be inferred from the ...

Abstract First‐principles computations are performed to investigate the catalytic oxidation of CO on a Ti‐decorated Cr 2 TiC O MXene monolayer, through comprehensive analysis charge transfer, electronic density states, and difference interacting systems. By comparing reaction energy barriers, it is found that, rather than traditional Langmuir–Hinshelwood, Eley–Rideal, Mars‐van Krevelen (MvK) me...

Abstract: The heat release capacity of polymers can be generally predicted using a method based on the additivity of group contributions (the Van Krevelen approach). Nevertheless, there are some exceptions, evidencing that this approach is insufficient and must be completed. In this study, the kinetic triplet accounting for the description of pyrolysis is identified for 11 polymers. Activation ...

Water oxidation is a crucial reaction for renewable energy conversion and storage. Among the alkaline oxygen evolution (OER) catalysts, NiFe based oxyhydroxides show highest catalytic activity. However, details of their OER mechanism are still unclear, due to elusive nature intermediates. Here, using novel differential electrochemical mass spectrometry (DEMS) cell interface, we performed isotop...

Abstract A kinetic model was developed by taking into account the dynamic nature of active sites in Mars–van Krevelen type catalytic reactions to predict evolution reactant and product composition gas phase CuCl2 concentration solid catalyst. The at steady-state ethylene oxychlorination obtained combining transient experiments two half-reactions redox cycle, namely reduced CuCl oxidation oxygen...

Co3Mo3N is one of the most active catalysts for ammonia synthesis; however, little is known about the atomistic details of N2 adsorption and activation. Here we examine whether N2 can adsorb and activate at nitrogen surface vacancies. We have identified the most favorable sites for surface nitrogen vacancy formation and have calculated vacancy formation free energies (and concentrations) taking...

A DFT modeling of the transition state of oxidative dehydrogenation of ethylbenzene over zirconium vanadate catalyst has been carried out. Computations confirm a Mars-Van-Krevelen type redox mechanism in which the catalyst abstracts a hydrogen atom from the hydrocarbon and catalyst is reduced. The reduced catalyst is reoxidized by oxygen from air. Computations suggest the formation of a hydroxy...