1. Laboratory for Optical Physics and Engineering CO + and C 2 Spectra Generated by CO 2 Atmospheric Pressure Glow Discharge in MicroChannels Chul Shin, Thomas J. Houlahan, Zhen Dai, Sung-Jin Park and J. Gary Eden University of Illinois 1406 W. Green St., Urbana, IL, 61801 June 16, 2014

2. Laboratory for Optical Physics and Engineering MOTIVATION Microcavity plasmas provide a unique platform for molecular spectroscopy: –Electron temperature of 1-10 eV –Specific power loadings up to 1 MW/cm 3 –Electron densities of 10 13 -10 17 cm -3 –Operating pressures up to and beyond 1 atm Demonstrate microplasma capacity with CO –Ionization potential of CO: ~14 eV Microplasmas are an efficient source of highly-excited diatomic neutrals and ions

3. Laboratory for Optical Physics and Engineering SYSTEM ARRANGEMENT CO 2 Ar H2H2 MFC Manometer Device Port Check Valve Vent Spectrophotometer (ICCD) Premixing Chamber Lens Optical Rail

4. Laboratory for Optical Physics and Engineering DEVICE DIMENSIONS 500 μm 100 μm 160 μm 40 μm Al 2 O 3 Al

5. Laboratory for Optical Physics and Engineering OPERATION AT ONE ATMOSPHERE - f = 20 kHz sine wave - V opeation ~2 kV rms 5 mm

6. Laboratory for Optical Physics and Engineering PANORAMIC: 320-670 nm

7. Laboratory for Optical Physics and Engineering COMET TAIL BAND SYSTEM 5 W, 60 SCCM CO 2

8. Laboratory for Optical Physics and Engineering SWAN SYSTEM 5 W, 60 SCCM CO 2

9. Laboratory for Optical Physics and Engineering POWER DEPENDENCE 60 SCCM CO 2

10. Laboratory for Optical Physics and Engineering POWER DEPENDENCE 60 SCCM CO 2

11. Laboratory for Optical Physics and Engineering SUMMARY Optical emission from dissociating pure CO 2 has been demonstrated CO + Comet Tail Band System dominates ultraviolet/visible emission Microplasmas are an efficient source of highly- excited diatomic neutrals and ions

12. Laboratory for Optical Physics and Engineering Thank You!

13. Laboratory for Optical Physics and Engineering REFERENCES [1] Pearse, R. W. B., Gaydon, A. G., Pearse, R. W. B., & Gaydon, A. G. (1976). The identification of molecular spectra (Vol. 297, p. 293). London: Chapman and Hall.

14. Laboratory for Optical Physics and Engineering OPTICAL EMISSION SPECTRUM OF CO 2 MICROPLASMA