Tin oxide microsensor arrays as probes for the oscillatory CO oxidation reaction on supported platinum

Micromachined sensor devices, capable of surface temperature control and electrical resistance measurements, have been used to detect and explore the oscillatory reaction of CO oxidation on SnO2-supported platinum films. Synchronization observed between oscillations for physically separated devices in a multielement array is evidence that the oscillations are due to bistable oxidation/reduction states coupled with a mass-transfer and reaction rate effect. In addition to the global synchronization, transient oscillations are observed prior to switching, which suggests that microscale coupling occurs between the individual platinum domains on the support.