TY - JOUR

T1 - Self-organization of ultrathin vanadium oxide layers on a Rh(111) surface during a catalytic reaction. Part I

T2 - A PEEM study

AU - Lovis, Florian

AU - Imbihl, Ronald

PY - 2011/10/6

Y1 - 2011/10/6

N2 - Self-organization of ultrathin vanadium oxide layers (θV < 0.5 MLE) on a Rh(111) surface during the H2 + O2 reaction has been investigated in the 10-6-10-4 mbar range using photoemission electron microscopy (PEEM) as a spatially resolving method. We observe that the homogeneous state is transformed via reaction fronts into macroscopic quasi-stationary patterns. In these patterns a condensation of V and O into stripes or islands takes place (θV < 0.5 MLE). The coarsening of the patterns with time follows a power-law dependence. The patterns are a nonequilibrium structure explained here tentatively as a result of reactive phase separation. Formation of the oxide distribution patterns is associated with a considerable memory effect. This memory effect can be exploited for microstructuring of the surface by applying a schedule for parameter variation. Decoration of such microstructures with nickel leads to channel-like structures through which pulses propagate during the H2 + O2 reaction.

AB - Self-organization of ultrathin vanadium oxide layers (θV < 0.5 MLE) on a Rh(111) surface during the H2 + O2 reaction has been investigated in the 10-6-10-4 mbar range using photoemission electron microscopy (PEEM) as a spatially resolving method. We observe that the homogeneous state is transformed via reaction fronts into macroscopic quasi-stationary patterns. In these patterns a condensation of V and O into stripes or islands takes place (θV < 0.5 MLE). The coarsening of the patterns with time follows a power-law dependence. The patterns are a nonequilibrium structure explained here tentatively as a result of reactive phase separation. Formation of the oxide distribution patterns is associated with a considerable memory effect. This memory effect can be exploited for microstructuring of the surface by applying a schedule for parameter variation. Decoration of such microstructures with nickel leads to channel-like structures through which pulses propagate during the H2 + O2 reaction.

UR - http://www.scopus.com/inward/record.url?scp=80053484746&partnerID=8YFLogxK

U2 - 10.1021/jp2065425

DO - 10.1021/jp2065425

M3 - Article

AN - SCOPUS:80053484746

VL - 115

SP - 19141

EP - 19148

JO - Journal of Physical Chemistry C

JF - Journal of Physical Chemistry C

SN - 1932-7447

IS - 39

ER -