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...

The catalytic oxidation of CO was performed over Au/TiO(2) under UV irradiation in the presence of H(2) in different reaction systems. It was found that the introduction of H(2) enhanced the CO thermocatalytic oxidation in a CO pre-introduced system (CO/O(2)vs. CO/H(2)/O(2)), but suppressed that in an O(2) pre-introduced (O(2)/CO vs. O(2)/H(2)/CO) system. Although the CO oxidation in both CO/H(...

Electrochemical techniques, coupled with in situ scanning tunneling microscopy, have been used to examine the mechanism of CO oxidation and the role of surface structure in promoting CO oxidation on well-ordered and disordered Pt(111) in aqueous NaOH solutions. Oxidation of CO occurs in two distinct potential regions: the prepeak (0.25-0.70 V) and the main peak (0.70 V and higher). The mechanis...

A series of nanostructured Pt-Au/MOx-CeO₂ (M = Mn, Fe, Ti) catalysts were prepared and their catalytic performance for the co-oxidation of carbon monoxide (CO) and hydrogen (H₂) were evaluated at room temperature. The results showed that MOx promoted the CO oxidation of Pt-Au/CeO₂, but only the TiO₂ could enhance co-oxidation of CO and H₂ over Pt-Au/CeO₂. Related characterizations were conducte...

In the autotrophic bacterium, Thiobacillus thiooxidans, the oxidation of sulfur is coupled to transfers of phosphate from the medium to the cells. CO(2) fixation is coupled to transfers of inorganic phosphate from the cells to the medium and is dependent, in the absence of concomitant sulfur oxidation, upon the amount of phosphate previously taken up during sulfur oxidation. The energy reservoi...

Co-oxidation is a little understood means of microbial degradation of petroleum hydrocarbons. In co-oxidation, microbes growing on one compound, the growth substrate, are able to oxidize a second · compound, the cosubstrate. This project examines the role of co-oxidation in the degradation of polycyclic aromatic hydrocarbons (PAR's), one of the most recalcitrant petroleum compounds now found in...

Four commercial monolithic diesel oxidation catalysts (DOCs) with two different platinum group metal (PGM) loadings and Pt:Pd ratios of 1:0, 2:1, 3:1 (w/w) were investigated systematically for CO, C3H6, NO oxidation, CO-C3H6 co-oxidation, CO-C3H6-NO reactions via transient activity measurements in a simulated engine exhaust environment. As PGM loading increased, light-off curves shifted to lowe...

Thin-film water oxidation catalysts (Co-Pi) prepared by electrodeposition from phosphate electrolyte and Co(NO(3))(2) have been characterized by electron paramagnetic resonance (EPR) spectroscopy. Co-Pi catalyst films exhibit EPR signals corresponding to populations of both Co(II) and Co(IV). As the deposition voltage is increased into the region where water oxidation prevails, the population o...