Autoreduction of Copper on Silica and Iron-Functionalized Silica Nanoparticles with Interparticle Mesoporosity

作者：Popova Margarita; Ristic Alenka; Mazaj Matjaz; Maucec Darja; Dimitrov Momtchil; Tusar Natasa Novak^*

来源：ChemCatChem, 2014, 6(1): 271-277.

DOI：10.1002/cctc.201300463

• copper autoreduction
• silica support
• iron-silica support
• silica nanoparticles
• interparticle mesoporosity

Copper-supported catalysts are of industrial importance in many catalytic processes. Mesoporous silica materials are of particular interest as green heterogeneous catalyst supports. In the present study we demonstrate the nature and reduction properties of copper oxide species, which are influenced by the peculiarity of the silica nanoparticles with interparticle mesoporosity (KIL family) and the presence of a second metal (iron) in the silica matrix. The copper-containing KIL-2 and FeKIL-2 samples are prepared by incipient wetness impregnation. The reduction of copper oxide species is easier on the FeKIL-2 supported sample in comparison to its KIL-2 supported analogue, whereas the copper-containing KIL-2 sample shows higher catalytic activity in total toluene oxidation. The presence of iron in the FeKIL-2 structure leads to autoreduction of copper followed by the redispersion and oxidation of metallic copper in the reaction medium; this results in the formation of different types of finely dispersed copper oxide species (<100nm). The later species possess lower catalytic activity in toluene oxidation in comparison to species that are 100nm in size and formed on KIL-2.

• 出版日期2014-1