Research Information System
Thesis Type: Doctorate
Institution Of The Thesis: Gazi Üniversitesi, Fen Bilimleri Enstitüsü, Turkey
Approval Date: 2013
Student: KIVILCIM KÖSEOĞLU
Supervisor: SELİM ACAR
Open Archive Collection: AVESIS Open Access Collection
Abstract:By integrating nanoporous zeolite material to the gas discharge structure for the first time, the current-voltage characteristics and gas discharge light emission (GDLE) were experimentally studied in a wide pressure range up to atmospheric pressure p (4-760 Torr), different interelectrode distances d (50-250 μm), and diameter D of the zeolite cathode (9-28 mm) in the planar gas discharge electronic device (GDED) with zeolite electrode at room temperature and in DC air microdischarges. But, the traditional semiconductor cathode device can not operate effective at atmospheric pressure, instead of a semiconductor, a dielectric (insulator) nanoporous zeolite was used which is an improvable advanced material. The system's efficient operation is based on the use of zeolite abundant naturally in Turkey, which is a good absorber of gas molecules in their nanoporous. Comparison of current and GDLE from GDED were examined for the determination of the homogeneity by the atmospheric pressure glow microdischarges. It was found that the GDLE inside the zeolite cathode develops from the surface if the amplitude of the applied voltage reaches to given threshold. Uniform GDLE could be generated in the air media at the atmospheric pressure. It has shown that, the GDED with zeolite cathode can serve as a source of UV-radiation with a large emitting area of zeolite cathode if gas pressure and electric field are sufficiently high. Optimal operation conditions determined for stable gas discharge (current-voltage and intensity-voltage). Current transmission processes were interpreted for GDED with zeolite cathode for the first time. Plasma-surface interactions mechanisms were described based on the properties of the zeolite materials. It has been shown that electronic conduction also added to ionic conduction which is occurring rare earth cations located in zeolite inner structure because of possibly electron multiplication in pores and gas discharge distance by using zeolite in GDED. Despite the running feedback voltage mode, sharp increase of current spontaneous mode has shown after reaching the high electric field, which is specific for zeolite electrode in GDED. Additionally, effect of zeolites cathode diameter change was examined. It was shown that breakdown voltage reduces significantly at atmospheric pressure when zeolite cathode with large diameter is used. By using the zeolite materials as a cathode in planar GDED, it is believed that the zeolite will improve microplasma devices which operate in low power comsumption, because of both reducing the breakdown voltage and generating GDLE in a stable, homogeneous and large emitting area in UV-visible region.