LIF Rotational Excitation Spectra Internal Gas Temperature Plasma- Catalytic Removal of Nitric Oxide Ellen R. Fisher, Department of Chemistry, Colorado State University Gas-phase nitrogen oxides (NOx) have been studied extensively because of their significant contribution to global air pollution. Despite gas phase studies showing decomposition into elemental components, substantial uncertainty remains about the fundamental mechanism of NOx conversion in plasma-catalytic processes. Using laser-induced fluorescence, we have performed gas-phase studies to gain a better understanding of the molecular level chemistry occurring. One type of information that we have acquired tells us how energy is partitioned among different plasma species. This often comes in the form of gas temperatures. Modeling of the rotational excitation spectra (center), acquired through images such as those shown (left), provide information on the internal temperature of NO in the plasmas. Making these measurements as a function of applied rf power (right) shows the differences between gas systems and suggests addition of non-reactive gases such as Ar serve to cool the molecules. NO LIF image LIF Rotational Excitation Spectra Internal Gas Temperature