Vanadium phosphorus oxides (VPO) has been applied as a heterogeneous catalyst in gas phase oxidation reactions and its application is very limited in liquid phase. In this study a series of cobalt-doped vanadium phosphorus oxides (VPO-Co) catalysts with different loading of Co (0.01-1.0 mol ratio of Co/V) were prepared. Oxidation of benzyl alcohol was studied in the liquid phase over VPO and VP...

In order to understand the mechanism of chemical reactions based on catalytic effects, such as, hydrogen (de)absorption and oxidation on a metallic crystal, it is important to study the processes at the atomic level. In-situ transmission electron microscopy (TEM) at pressures (1-10 bar) of gas is expected to provide the most direct information. Such a pressure in combination with the high vacuu...

[1] Secondary organic aerosol (SOA) formed from partitioning of oxidation products of anthropogenic and biogenic volatile organic compounds (VOCs) accounts for a substantial portion of atmospheric particulate matter. In describing SOA formation, it is generally assumed that VOC oxidation products rapidly adopt gas-aerosol equilibrium. Here we estimate the equilibration timescale, teq, of SOA ga...

Rates of nitrogen dioxide (NO2) absorption and sulfide oxidation were measured in a highly characterized stirred cell contactor at 55 °C, with O2 present in the gas phase. The rate constant of the reaction between NO2 and sul-fide at 55 °C was determined to be 26.4 x105 M-1sec-1. A reaction mechanism was proposed that is consistent with the kinetic data. NO2 absorption initiates sulfide oxidati...

Secondary Organic Aerosols (SOA) are formed by condensation of multifunctional species produced during gaseous oxidation of Volatile Organic Compounds (VOC). The Generator for Explicit Chemistry and Kinetics of Organics in the Atmosphere (GECKO-A) has been developed to describe highly detailed gas phase oxidation schemes for organic compounds under general tropospheric conditions and the partit...

Density functional theory calculations on oxygen adsorption over gas phase and faujasite supported Au monomer has been studied using hybrid quantum mechanics∕molecular mechanics method, surface integrated molecular orbital molecular mechanics implemented in GAMESS package. Three different oxidation states of Au (0, +1, +3) and three different adsorption modes viz., top, bridge, and dissociative...

The mechanisms of formic acid (HCOOH) oxidation on Au(111) under gas-phase and electrochemical conditions was studied by using density functional theory and then compared with the analogous processes on Pt(111). Our results demonstrate that a mechanism involving a single intermediate molecule is preferred on both Au and Pt(111). Furthermore, under gas-phase conditions, HCOOH oxidation proceeds ...

In this study, we applied cluster beam deposition (CBD) as a new approach for fabricating efficient plasmon-based photocatalytic materials. Au nanoclusters (AuNCs) produced in the gas phase were deposited on TiO₂ P25-coated silicon wafers with coverage ranging from 2 to 8 atomic monolayer (ML) equivalents. Scanning Electron Microscopy (SEM) images of the AuNCs modified TiO₂ P25 films show that ...

This paper considers the gas phase chemistry in a protoplanetary accretion disk, especially the chemistry initiated in the gas phase by destruction of dust close to the central star. Slow radial particle transport moves gas and dust from the cold outer parts of a protoplanetary accretion disk into its warm central part where chemical reactions in the gas phase are activated. At the same time ga...

[1] To investigate the major sources of summertime organic aerosol (OA) and provide insights into secondary organic aerosol (SOA) formation, positive matrix factorization analysis was performed on a large set of organic species measured during the California at the Nexus of Air Quality and Climate Change (CalNex) campaign in Bakersfield, CA. Six OA source factors were identified, including one ...