We are investigating catalytically enhanced production of singlet oxygen, O2(a1▵g), observed by reaction of O2/He
discharge effluents over an iodine oxide film surface in a microwave discharge-flow reactor at 320 K. We have
previously reported a two-fold increase in the O2(a) yields by this process, and corresponding enhancement of I(2P1/2)
excitation and small-signal gain upon injection of I2 and NO2. In this paper we review observed I* excitation behavior and
correlations of the catalytically generated O2(a) with atomic oxygen over a large range of discharge-flow conditions to develop
a conceptual reaction mechanism for the phenomena. We describe a first-generation catalytic module for the PSI supersonic
MIDJet/EOIL reactor, and tests with this module for catalyst coating deposition and enhancement of the small-signal gain
observed in the supersonic flow. The results present compelling evidence for catalytic production of vibrationally excited
O2(X,v) and its participation in the I* excitation process. The observed catalytic effects could significantly benefit the
development of high-power electrically driven oxygen-iodine laser systems.
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