Facile synthesis of highly dispersed and thermally stable copper-based nanoparticles supported on SBA-15 occluded with P123 surfactant for catalytic applications

Chirieac, Alexandru;Dragoi, Brindusa;Ungureanu, Adrian;Ciotonea, Carmen;Mazilu, Irina;Royer, Sebastien;Mamede, Anne Sophie;ROMBI, ELISABETTA;FERINO, ITALO;Dumitriu, Emil

2016-01-01

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Abstract

Here, we show a strategy to control the dispersion, spatial distribution, and stabilization of copper-based nanoparticles on a micro-mesoporous silica support, as well as their impact on the catalytic activity. In this respect, SBA-15 with P123 occluded mesopores was used as host to load, by impregnation, copper-based nanoparticles, whose dispersion was similar to that of the homologous NPs prepared by precipitation on the SBA-15 with open mesoporosity, while the thermal stability was better. The oxide and reduced forms of the catalysts were rigorously characterized by ICP-OES, low- and high-angle XRD, N2 physisorption, HRTEM/EDXS, TPR, in situ XRD, and in situ XPS. Due to their high practical impact, both the oxide and metallic forms of the copper-based NPs were evaluated for catalytic activity in CO oxidation and hydrogenation of cinnamaldehyde, respectively. It was shown that the high dispersion of copper-based NPs and the electron-deficient sites, such as M2+ with high affinity for the C=O bond, are responsible for the outstanding catalytic performance of the solids. The paper demonstrates that using a simple impregnation method and a functionalized SBA-15 support, high-performance materials can be obtained avoiding the use of precipitating agents and strict control of the synthesis conditions.