Large amplitude excitations traveling along the interface in bistable catalytic methanol oxidation on Rh(110).

Traveling interface modulations have been observed in catalytic methanol oxidation on an unpromoted Rh(110) and a partially vanadium oxide covered (θV = 0.1 MLE) Rh(110) surface. The front instabilities have been followed with photoemission electron microscopy (PEEM) in the 10-4 mbar range at T ≈ 800 K where the reaction is bistable. Near the equistability point large amplitude excursions (up to 300 μm) from the average interface position occur which travel in a pulse-like manner along the interface.