Bimetallic Pd–Sn catalysts were synthesized by incipient-wetness impregnation of the metals on al... more Bimetallic Pd–Sn catalysts were synthesized by incipient-wetness impregnation of the metals on alumina and employed for the reduction of nitrates from aqueous solutions. The catalysts were characterized by FTIR spectroscopy of adsorbed CO, X-ray diffraction (XRD), transmission electron microscopy (TEM), and H2 chemisorption. The influence of the metal ratio was evaluated in reaction measurements. The bimetallic Pd–Sn catalysts exhibited high selectivity for nitrate removal forming less NO 2− and NH 4+ than the Pd–Cu catalysts.
A Pd/SnO2 catalyst was doped with low concentrations of Bi in order to induce selective poisoning... more A Pd/SnO2 catalyst was doped with low concentrations of Bi in order to induce selective poisoning of sites on the Pd surface in order to test a hypothesis that specific surface sites are responsible for ammonium formation during the catalytic hydrogenation of nitrates ...
Detection of mobile charge carriers consistent with a process involving electron transfer from Ti... more Detection of mobile charge carriers consistent with a process involving electron transfer from TiO 2 to metal particle was measured by EPR and FTIR in the presence of a hole scavenger and under UV irradiation. The main role of the metal (Ag, Au or Cu) was to scavenge the ...
Pd/TiO2 catalysts were found to enter an strong metal support interaction (SMSI) state after redu... more Pd/TiO2 catalysts were found to enter an strong metal support interaction (SMSI) state after reduction at temperatures as low as 473 K. This was identified as a significant loss in the CO uptake as monitored by low temperature FTIR. Electron microscopy provides direct evidence of the presence of ordered, reduced titanium oxide layers over palladium (SMSI state) for Pd/TiO2 catalysts following reduction at temperature 623 K. The crystal phase was identified as Ti4O7 and this phase, once formed, was found to be stable even after exposure to atmospheric conditions.
Bimetallic Pd–Sn catalysts were synthesized by incipient-wetness impregnation of the metals on al... more Bimetallic Pd–Sn catalysts were synthesized by incipient-wetness impregnation of the metals on alumina and employed for the reduction of nitrates from aqueous solutions. The catalysts were characterized by FTIR spectroscopy of adsorbed CO, X-ray diffraction (XRD), transmission electron microscopy (TEM), and H2 chemisorption. The influence of the metal ratio was evaluated in reaction measurements. The bimetallic Pd–Sn catalysts exhibited high selectivity for nitrate removal forming less NO 2− and NH 4+ than the Pd–Cu catalysts.
A Pd/SnO2 catalyst was doped with low concentrations of Bi in order to induce selective poisoning... more A Pd/SnO2 catalyst was doped with low concentrations of Bi in order to induce selective poisoning of sites on the Pd surface in order to test a hypothesis that specific surface sites are responsible for ammonium formation during the catalytic hydrogenation of nitrates ...
Detection of mobile charge carriers consistent with a process involving electron transfer from Ti... more Detection of mobile charge carriers consistent with a process involving electron transfer from TiO 2 to metal particle was measured by EPR and FTIR in the presence of a hole scavenger and under UV irradiation. The main role of the metal (Ag, Au or Cu) was to scavenge the ...
Pd/TiO2 catalysts were found to enter an strong metal support interaction (SMSI) state after redu... more Pd/TiO2 catalysts were found to enter an strong metal support interaction (SMSI) state after reduction at temperatures as low as 473 K. This was identified as a significant loss in the CO uptake as monitored by low temperature FTIR. Electron microscopy provides direct evidence of the presence of ordered, reduced titanium oxide layers over palladium (SMSI state) for Pd/TiO2 catalysts following reduction at temperature 623 K. The crystal phase was identified as Ti4O7 and this phase, once formed, was found to be stable even after exposure to atmospheric conditions.
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