High-voltage Electrode Materials Research Articles

Design of a DBD wire-cylinder reactor for NO x emission control: experimental and modelling approach

The objective of this work was to develop a wire-cylinder dielectric barrier discharge reactor for NO x removal from a gas mixture simulating exhaust gases. NO conversion was investigated as a function of parameters such as high voltage (HV) electrode material, dielectric material, NO concentration and reactor gap. A complete decomposition path is proposed from 18O 2 isotope experiments. Finally, a model consisting of ‘Continuous Stirred Tank Reactors’ (CSTR) cascade with multiple injections of atomic oxygen is proposed in order to explain the relationships between the reactor parameters (inlet flow, inlet NO concentration, electrical energy density and electrical gap) and the experimental results (outlet NO x concentration). Optimization of the model parameters permitted the authors to fit experimental and calculated results with a maximum absolute error of about 5% on NO conversion.

Amorphous Li–V–Si–O Thin Films as High-Voltage Negative Electrode Materials for Thin-Film Rechargeable Lithium-Ion Batteries

A new kind of high-voltage negative electrode material for thin-film rechargeable lithium-ion batteries was prepared through electrochemically reductive decomposition of an amorphous Li–V–Si–O thin solid electrolyte film. The thin solid electrolyte film was prepared by pulsed laser deposition, showing in ionic conductivity with negligible electronic conductivity. Electrochemical lithium insertion into the thin solid electrolyte film was observed at ca. (vs ), which was the potential window of the reduction side for the film electrolyte. When the lithium insertion∕extraction reaction was repeated over the reductive-side potential window (1.0–4.0 vs ) at low current density, the charge∕discharge capacity gradually increased with the repetition of the reaction. Consequently, large charge∕discharge capacity was achieved under quasi-open-circuit voltage conditions between 1.2 and (vs ). X-ray photoelectron spectroscopy analysis revealed that the redox reaction of vanadium ions in the film compensated the electrical charge balance for the lithium insertion∕extraction reaction of the film electrolyte. The apparent lithium diffusion coefficient of the film was .

Degradation of Aqueous Phase Polychlorinated Biphenyls (PCB) Using Pulsed Corona Discharges

AbstractThe efficacy of pulsed corona discharges, an effective technique for removal of small aromatic and volatile organic compounds in water, to degrade aqueous phase polychlorinated biphenyls (PCB) was tested. Experiments were conducted on the model PCB compound, 2,2′,4,4′- tetrachlorobiphenyl at its solubility limit (68 ppb) in water. The effects of various reactor configurations featuring liquid and combined liquid/gas discharges on the degradation rate and possible degradation mechanisms of the PCB congener were determined. The pulsed corona reactor led to nearly 70% degradation of the PCB congener within 60 min. Increased degradation rates due to the Fenton’s reactions were found upon the addition of ferrous salts in solution, and the degradation rate of the PCB was higher than those of phenol and nitrobenzene in the absence of ferrous salts. The two different reactor configurations tested, including direct discharge in water and simultaneous gas-liquid discharge, gave the same rate of PCB degradation in the Fenton’s case, thus raising the possibility that the PCB degradation mechanisms in both reactors are the same. The effect of the high voltage electrode material on the degradation of PCB was evaluated by performing experiments with electrodes made of either platinum or a nickel-chromium alloy.