Electronics of Supported Catalysts

Interaction of nanostructured metal overlayers with oxide surfaces

“…An alternative route towards the fabrication of model systems is the deposition of nanostructured oxide layers on well-defined metal surfaces. This process forms an inverse model system, which has been useful to explore the metal-oxide interactions [7,196,197]. In case of electronic interaction between metals and oxide supports, the ratio of the amount of metal to that of semiconducting oxide support must be very small (e.g., very small metal clusters on large oxide) such that the transferred charge to or from the metal is sufficient to affect the electronic structure of the metal, such as the metal Fermi Energy.…”

“…In an inverse model system, the very large number of electrons in the metal support can easily modify the electronic structure of the supported semiconducting oxide layer. The electronic interaction between the two phases becomes more significant such that the interaction can be easily probed [7].…”

“…Many catalytic systems consist of nanosized metal catalysts supported on oxides. It has been found that the interaction between metals and oxide supports, so-called metal-support interactions, are of great importance in heterogeneous catalysis [6][7][8][9][10][11][12][13]. In particular, the strong metal-support interaction (SMSI) was first suggested by Tauster et al to explain the suppression of both H 2 and CO chemisorption capacity of metal clusters supported on TiO 2 which are reduced at high temperatures [14,15].…”

Inverse Oxide/Metal Catalysts in Fundamental Studies and Practical Applications: A Perspective of Recent Developments

“…Thus, an oxide/metal configuration maybe more common in heterogeneous catalysts than expected. 9,21,22,26,27 For all of these reasons, in this article we present a perspective on the use of inverse oxide/metal catalysts in fundamental studies and practical applications.An understanding of the behavior of inverse oxide/metal catalysts requires a fundamental knowledge of their structural and electronic properties. In the area of conventional metal/oxide catalysts, a lot of research has been aimed at understanding the effects of strong metal-support interactions (SMSIs) on the structural, electronic and chemical properties of the supported metal.…”

Katalizátorok felületének jellemzése röntgen-fotoelektron spektroszkópiával

“…Ha a fémrészecskék mérete a nanométeres tartományba esik, olyan új fizikai és kémiai tulajdonságok jelennek meg, melyekkel a tömbfázisbeli anyag nem rendelkezik. Ezzel párhuzamosan a fém és a hordozó közötti kölcsönhatás egyre fontosabb szerepet játszik a heterogén katalitikus folyamatok értelmezé-sében [1][2][3]. Általában igaz, hogy a katalizátorok aktivitása és szelektivitása összefüggésben van a részecskemérettel, a felületi fématomok és a tömbfázisbeliek arányával [4].…”