title: Reduction of breakdown threshold by metal nanoparticle seeding in a DC microdischarge.
abstract: Significant reduction of the breakdown threshold in a DC microdischarge via seeding metal nanoparticles has been demonstrated. Compared to standard Paschen curves in dry air, reductions in the breakdown voltage of 5% to 25% were obtained for PD values (the product of pressure and electrode gap distance) ranging from 20 to 40 Torr-cm by seeding aluminum and iron nanoparticles with mean sizes of 75 nm and 80 nm, respectively. No secondary energy source was required to achieve this breakdown threshold reduction. From high-speed chemiluminescence imaging of the discharge evolution, breakdown was shown to be initiated at reduced voltages. Following breakdown, the increase in temperature ignited some of the nanoparticles near the cathode. Results suggest that possible charging of the nanoparticles within the gap may reduce the effective transient distance, leading to the threshold reduction.
authors: Department of Mechanical, Aerospace and Biomedical Engineering, University of Tennessee, Knoxville, TN 37996 USA.
authors: Jordan
authors: J
authors: Sawyer
authors: Department of Mechanical, Aerospace and Biomedical Engineering, University of Tennessee, Knoxville, TN 37996 USA.
authors: Jacques
authors: J
authors: Abboud
authors: Department of Mechanical, Aerospace and Biomedical Engineering, University of Tennessee, Knoxville, TN 37996 USA.
authors: Zhili
authors: Z
authors: Zhang
authors: Air Force Research Laboratory (AFRL/RQQE), Wright-Patterson AFB, Dayton, OH 45433-7919 USA.
authors: Steven F
authors: SF
authors: Adams
keywords: Metal nanoparticles; Microdischarge; Threshold