Supported complexes comparison with surfaces

Second, apart from single crystals, nanoparticle model catalysts should be employed to better mimic the complex properties of supported metals. Nevertheless, the metal nanoparticles should still exhibit well-defined surface facets to allow more reliable data interpretation and a comparison with single-crystal results. 

In addition to the supporting self-citations [742,6,457,330], there was much early support for the formation of donor-acceptor complexes. Radke and Praus-nitz [743] interpreted the extensive loadings of phenols even at very low concentrations, in comparison with lower uptakes of several aliphatic adsorbates, as evidence for specific interaction with the activated carbon surface. Barton and Harrison [744] studied the effect of graphite outgassing temperature on the heat of immersion of benzene and attributed a shallow minimum at ca. 800°C to the effect of CO desorption, thus implicitly supporting the donor-acceptor complex proposal in terms of a reduction in the interaction between the partial charge on the carbonyl carbon atom and the 7t-electron cloud of the benzene molecule. ... 

The catalytic performances of LaxMOy oxides could be considerably improved if they were incorporated in a support allowing to enhance selectivity and dispersion. Indeed, previous attempts showed a noticeable increase of the surface area and catalytic activity of perovskite pillared montmorillonite in comparison with pure perovskite [3]. Therefore, we were interested in elaborating nanocomposites made of LaxMOy oxides dispersed in a layered silicate matrix. For that, we used a process based on the Cationic Exchange Capacity (CEC) of Na-Montmorillonite the sodium cations are exchanged with heterobinuclear complex cations and subsequent heat treatment leads to the nanocomposite [4]. 

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