19 research outputs found
Light emission from heteronuclear Ar-Kr doubly ionized excimer molecules
Light emission from a ~100 mbar Ar-Kr mixture excited by a pulsed discharge is
described. The discharge was arranged to form a homogeneous cathode layer and spatial
filtering was used to measure time-dependent spectra emitted from a region where electrons
accelerated in the cathode sheath induce the light emission. Novel excimer bands were
observed around a wavelength of 315 nm in addition to the better known so called third
excimer continua of Ar and Kr. A tentative assignment for these bands to charge-transfer
transitions: ArKr2+ → Kr+ + Ar+ + hν is provided and discussed in the context of earlier works on
heteronuclear ionic excimer molecules. Predictions for the wavelength positions of similar
emission bands are provided for other combinations of noble gases. The rate constants for
the formation of heteronuclear ArKr2+ excimers in three-body reactions and
two-body collisional quenching of Kr2+∗ ions by Ar atoms have been determined
from the time dependence of the ArKr2+ emission
Data of oxygen reduction reaction on Pd nanocatalysts prepared by plasma-assisted synthesis on different carbon nanomaterials
This dataset contains the data presented in the figures of published paper "Oxygen reduction reaction on Pd nanocatalysts prepared by plasma-assisted synthesis on different carbon nanomaterials" Nanotechnology 32 035401 (https://doi.org/10.1088/1361-6528/abbd6f
Cobalt-Containing Nitrogen-Doped Carbon Materials Derived from Saccharides as Efficient Electrocatalysts for Oxygen Reduction Reaction
The development of non-precious metal electrocatalysts towards oxygen reduction reaction (ORR) is crucial for the commercialisation of polymer electrolyte fuel cells. In this work, cobalt-containing nitrogen-doped porous carbon materials were prepared by a pyrolysis of mixtures of saccharides, cobalt nitrate and dicyandiamide, which acts as a precursor for reactive carbon nitride template and a nitrogen source. The rotating disk electrode (RDE) experiments in 0.1 M KOH solution showed that the glucose-derived material with optimised cobalt content had excellent ORR activity, which was comparable to that of 20 wt% Pt/C catalyst. In addition, the catalyst exhibited high tolerance to methanol, good stability in short-time potential cycling test and low peroxide yield. The materials derived from xylan, xylose and cyclodextrin displayed similar activities, indicating that various saccharides can be used as inexpensive and sustainable precursors to synthesise active catalyst materials for anion exchange membrane fuel cells
Temporal response of UV sensors made of highly oriented diamond films by 193 and 313 nm laser pulses
International audienceUltraviolet sensors were fabricated on a Si substrate using an undoped, highly oriented diamond film with Pt and Al interdigited electrodes with a gap length of 5, 10 and 15 m. Transient voltage outputs due to photocurrent of the sensors under Ž a bias voltage of 20, 40 and 80 V were measured by the pulsed irradiation of an ArF excimer laser s 193 nm, pulse widths 5. Ž. ns or a dye laser s 313 nm, pulse widths 7 ns. It was found that the transient voltage output by the ArF laser irradiation on Ž. a sensor Pt electrodes with a 15-m gap consisted of main and second peaks at 1.1 and 3.8 ns, respectively, when the bias voltage was 20 V. The FWHM was approximately 4 ns. The second peak was observed in the output signals of most sensors. On the other hand, the voltage output was two orders of magnitude weaker when the sensors were irradiated by the dye laser
Cobalt-Containing Nitrogen-Doped Carbon Materials Derived from Saccharides as Efficient Electrocatalysts for Oxygen Reduction Reaction
The development of non-precious metal electrocatalysts towards oxygen reduction reaction (ORR) is crucial for the commercialisation of polymer electrolyte fuel cells. In this work, cobalt-containing nitrogen-doped porous carbon materials were prepared by a pyrolysis of mixtures of saccharides, cobalt nitrate and dicyandiamide, which acts as a precursor for reactive carbon nitride template and a nitrogen source. The rotating disk electrode (RDE) experiments in 0.1 M KOH solution showed that the glucose-derived material with optimised cobalt content had excellent ORR activity, which was comparable to that of 20 wt% Pt/C catalyst. In addition, the catalyst exhibited high tolerance to methanol, good stability in short-time potential cycling test and low peroxide yield. The materials derived from xylan, xylose and cyclodextrin displayed similar activities, indicating that various saccharides can be used as inexpensive and sustainable precursors to synthesise active catalyst materials for anion exchange membrane fuel cells
Data of transition metal phthalocyanine-modified shungite-based cathode catalysts for alkaline membrane fuel cell
This dataset contains the data presented in the figures of pulbished paper "Transition metal phthalocyanine-modified shungite-based cathode catalysts for alkaline membrane fuel cell" International Journal of Hydrogen Energy 46, 4365-4377 (https://doi.org/10.1016/j.ijhydene.2020.10.231)
The electrochemical characterisation data, which was measured in University of Tartu Institute of Chemistry, is for Figures 5, 6, 7, 9, 10, S2, S3, S4 and the nomenclature of the catalysts is the same as in the mentioned article
Data of Iron-Containing Nitrogen-Doped Carbon Nanomaterials Prepared via NaCl Template as Efficient Electrocatalysts for the Oxygen Reduction Reaction
The dataset contains the data presented in the figures of published paper:
"Iron-Containing Nitrogen-Doped Carbon Nanomaterials Prepared via NaCl Template as Efficient Electrocatalysts for Oxygen Reduction Reaction", ChemElectroChem 8 (2021) 2288-2297 (https://doi.org/10.1002/celc.202100571
Data of polypyrrole and polythiophene modified carbon nanotube-based cathode catalysts for anion exchange membrane fuel cell
This dataset contains the data presented in the figures of pulbished paper "Polypyrrole and polythiophene modified carbon nanotube-based cathode catalysts for anion exchange membrane fuel cell" ChemElectroChem 9 e202200161 (https://doi.org/10.1002/celc.202200161)
The electrochemical characterisation data, which was measured in University of Tartu Institute of Chemistry, is for Figures 1,2,3a,4a, 9, S1 and the nomenclature of the catalysts is the same as in the mentioned article