Isotopes in Heterogeneous Catalysis

Surface properties and thermal stability of SiO2-crystalline TiO2 nano-composites

“…This titania accessibility is a key parameter since the exchange reaction mechanism supposes adsorption and dissociation of the 18 O 2 molecules on the oxide support. 84 In conclusion, high oxygen mobilities are obtained for the two samples presenting limited sintering, showing the high reactivity of titania nanodomains.…”

Adsorption/Desorption Behavior of Ethanol Steam Reforming Reactants and Intermediates over Supported Cobalt Catalysts

“…The rationale behind this experiment was to identify the source of the surface hydroxyl groups by making use of the isotopic shift that would be expected in the IR bands when hydroxyl (OH) groups are replaced by OD groups. Figure 2b shows the OH band that appeared in the 3,700-3,200 cm -1 region shifts to lower frequencies by about 1,000 cm -1 when D 2 O is used, exhibiting the isotopic shift one would expect to see between OH and OD groups in the IR spectra [41]. Simultaneously the peak due to the molecularly adsorbed D 2 O was observed to shift from 1,650 cm -1 in the H 2 O adsorption to 1,581 cm -1 .…”

Molecular Reactions of O2 and CO2 on Ionically Conducting Catalyst

“…In this work, surface reaction kinetics on Ba 0.5 Sr 0.5 Co 0.8 Fe 0.2 O 3‑δ (BSCF) is investigated via gas-phase oxygen isotope exchange. Although BSCF has been demonstrated to have remarkable performance due to extraordinary surface catalytic activity for both the oxygen reduction and evolution reactions (ORR/OER), ,,,− the stability of BSCF in CO 2 environments is still a major issue for practical applications. For BSCF, it was found previously that CO 2 prefers to bond to the alkaline-earth metals, Ba and Sr, occupying the A-site in the ABO 3 perovskite.…”