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Electron emission characteristics of low work function surfaces - total energy distributions for five crystallographic directions of tungsten
Vacuum thermionic work functions of polycrystalline Be, Ti, Cr, Fe, Ni, Cu, Pt and type 304 stainless steel
Literature search of physical property data and composite surface work function models
Photoelectric scanning device maps the work function of a metal surface by scanning it with a light spot and measuring the resulting photocurrent. The device is capable of use over a range of surface temperatures.
Quality and stability of electron emission characteristics of low work function surfaces - tungsten
Thermionic work function of refractory intermetallic compounds and their electronic and crystal structures
Radioactive tracer and work function of chemisorption of gas on metal
Work function and desorption energy measurements of alkali metals from metallic substrates with modulated molecular beam, noting surface contamination
Self-heating hollow cathodes are central components in modern electric thrusters. The plasma discharge inside these devices heats the internal components, thus maintaining the temperatures required for electron emission. Precise knowledge of the physical phenomena governing hollow cathode operation is key to predict their lifetime, specifically, their thermionic emission characteristics. A simulation platform has been built to couple plasma and thermal models of the self-heating hollow cathode to produce a self-consistent solution. A self-consistent solution has been found for a LaB6 hollow cathode operating at 25A and 13 sccm where the work function is assumed to be spatially uniform along the emitter with a value which is allowed to vary as the coupled model iterates to a self-consistent solution. The emitter temperature from the converged solution does not agree with experimental temperature measurements, however. The results of a sensitivity analysis suggest that none of the tolerances in the measurement are responsible for the discrepancy. We hypothesize that either the work function needs to be a function of position along the emitting surfaces or the heat fluxes have been overestimated in the plasma solver.
Vacuum thermionic work function and thermal stability measurements on crystal surfaces, discussing results on carbides, diborides and disilicades
Desorption, mobility and work function change of mercury on tungsten and molybdenum substrates
Electric fields and electron work functions, surface potentials and number density distributions in selected metals surfaces determined using free electron model
Coadsorption of cesium and fluorine on tungsten, and analysis of mechanisms leading to decay of field emission current from low work function zirconium/oxygen coated tungsten emitter
Total energy distribution of field emitted electrons and single plane work functions for tungsten, discussing correspondence with Fowler-Nordheim models for field emission
Free electron model for electron work functions and number density distributions and surface potentials in metals
Determining work functions and temperature coefficients by relative field emission method
The variations of the thermoelectronic work function of titanium dioxide, submitted to an ultraviolet or visible and infrared radiation, in the presence of oxygen, are studied by the vibrating condenser method. It is shown that during the ultraviolet irradiation, a desorption of a first species of oxygen simultaneously occurs with the adsorption of a second species of oxygen and that this phenomenon is found for any structure of TiO2 (anatase or rutile) any texture, oxygen pressure, radiation intensity, and nature of introduced dopes.
The study of the variation of thermoelectronic work function potential of TiO2 in the presence of isobutane shows that this gas is not adsorbed on this solid, in either the presence or the absence of ultraviolet radiation. These results, as well as those obtained in a previous work, lead to the mechanism of the photo-oxidation of isobutane at room temperature, in which excited atomic oxygen is the active species.