Pattern formation in restricted geometries: The NO+CO reaction on Pt(100)

Employing photoelectron emission microscopy (PEEM) as the spatially resolvi ng technique, pattern formation during the catalytic reduction of NO with C O has been investigated on a microstructured Pt(100)/Ti/TiO2 surface in the 10(-6) and 10(-5) mbar range. The microstructured surface-initially create d by a lithographic technique-shows restricted Pt(100) domains of varying s ize and geometry, such as circles, rings, and dumbbells, surrounded by an i nert Ti/TiO2 layer. It is shown that pattern formation during the NO+CO rea ction, i.e., the propagation of pulses on the Pt(100) surface, is significa ntly affected by the size and the geometry of these domains. (C) 2000 Ameri can Institute of Physics. [S0021- 9606(00)70715-X].