Theoretical And Experimental Research On Gas-discharged Singlet Delta Oxygen Generator

Recently, Chemical Oxygen-Iodine Laser(COIL) has raised much more attention because of its short wavelength, high efficiency and good performance in fiber transmission. COIL is obtained by the near resonant energy transfer between singlet-delta oxygen O2(1△) and atomic iodine, and the generation of O2(1△) is one of the important parts. Traditionally O2(1△) is produced by a typical chemical gas-liquid reaction system, while recent efforts have been put on the new kinds of singlet-delta oxygen generators which are all gas phase and electrical discharged, it is the gas-discharged singlet-delta oxygen generator. In this thesis, both theoretical and expermental studies of gas-discharged singlet-delta oxygen generator have been carried, and details are as follows:(1) The theoretical study of RF discharged oxygen plasma in slab structure has been carried out. According to the continuity equation of electron density, the electron energy equilibrium equation and the continuity equation of current density, the spatial distributions of electron density, electric field, electron mean energy and excitation efficiency of singlet delta oxygen are obtained. The effects of current density, excitation frequency and gas pressure on discharge characteristics have been analyzed. We also used another model to calculate the spatial distributions of electron, positive ion and electron energy which all change with RF period.(2) The electron mean energy in the RF-discharged oxygen plasma were studied theoretically and experimentally. The electron mean energy in O2 and its mixtures was obtained by solving Boltzmann equation, and the effects of gas mixture have been studied. And the experiments of the Langmuir probe system and spectral analysis on electron mean energy were carried out.(3) The experiments of RF discharged singlet delta oxygen generator in slab structure have been done. The O2(1△)'s spectra line at 1268nm has been observed, the feasibility of this generator was proved. As O2(1∑) and atomic oxygen have great influence on the yield of O2(1△), the visible spectrum of O2(1∑) and O have also been measured, and in pure O2 and its mixtures the effects on these particles have been discussed.(4) The pulse discharged singlet delta oxygen generator has been studied experimentally. In contrast with low pressure in RF discharged generator, steady discharge has been sucessfully obtained in high pressure of hundreds of mBar (up to 1000mBar). The particle density, reduced electric field(E/N) and plasma photos have all been studied to show the advantage of higher pressure. Time behaviors of O2(1∑) and O have also been measured.