Single crystal clean work functions and the behavior of various adsorbates on metal surfaces Final report
Determining work functions and temperature coefficients by relative field emission method
Bell, A. E.↗
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Change in the thermionic work function of semiconductor powders exposed to electromagnetic radiation
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.
Bourasseau, S.↗
Variation in the thermionic work function of semiconductor powders exposed to electromagnetic radiation
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.
Bourasseau, S.↗
Work Function Tuning of a Weak Adhesion Homojunction for Stable Perovskite Solar Cells
Perovskite solar cells (PSCs) have demonstrated a comparable efficiency to Si-based cells. However, the buried interface with weak adhesion remains a critical issue since the ion migration enhanced by the built-in electric field at this interface might lead to instability. We report here that adjusting the energy-level alignment at the weak adhesion homojunction interface can mitigate ion migration and thereby enhance the stability and photovoltaic performance of PSCs. Functional molecules with self-assembled monolayer characteristics were introduced to the surface of the SnO2 layer using silane derivatives, which tuned the work function of the homojunction depending on the functional groups in the molecules and thereby significantly reduced the built-in electric field. The PSC exhibited a power conversion efficiency (PCE) of 25.3%. The maximum power point (MPP) tracking under continuous illumination confirmed that the device retained more than 97% of its initial PCE, even after 1,000 h.
homojunction↗
Investigations of electron emission characteristics of low work function surfaces Final report, 28 Sep. 1966 - 13 Nov. 1967
Electron emission characteristics of low work function surfaces
Bell, A. E.↗
Single plane work function coverage relationships for cesium and oxygen coadsorbed on tungsten
Probe field emission studies of work function and energy distribution of cesium-oxygen-tungsten system
Source record↗
The work function determination and surface characterization of vapor deposited rhenium.
Vapor deposited rhenium surface characteristics and work functions obtained from 1800 to 2300 degrees K by X ray diffraction analysis
Campbell, A. E., Jr.↗
Performance of a cylindrical geometry thermionic converter with an improved work function tungsten emitter.
Cylindrical geometry thermionic converter with vapor deposited W emitter, noting power density performance characteristics, work function and long term stability
Holland, J. W.↗
Surface cleanliness research using the work function technique Final report
Argon ion bombardment and other surface cleaning methods evaluated on polycrystalline tungsten by work function techniques
Brock, F. J.↗
Work function measurements by the field emission retarding potential method
Using the field emission retarding potential method true work functions have been measured for the following monocrystalline substrates: W(110), W(111), W(100), Nb(100), Ni(100), Cu(100), Ir(110) and Ir(111). The electron elastic and inelastic reflection coefficients from several of these surfaces have also been examined near zero primary beam energy.
Swanson, L. W.↗
Question on the measurement of the metal work function in an electron spectrometer by the secondary-electron emission threshold method
The feasibility of measuring metal work functions using the secondary emission threshold method and an electron spectrometer is demonstrated. Measurements are reported for Nb, Mo, Ta, and W bombarded by Ar(+) ions.
Alov, N. V.↗
Electron theory of metals, bases on Fermi statistics. Part I - General data, flow processes, and work functions
Electron theory of metals based on Fermi statistics and Bose-Einstein statistics - general data, flow processes, and work functions
METAL↗
<theoretical studies on the relationship between the thermionic work function of re- fractory intermetallic compounds and their electronic and crystal structures< progress report letter, 1 jul. - 31 dec. 1964
Thermionic work function of refractory metallic compounds and electronic and crystal structure - emissivity measurement and diode fabrication
DIODE↗
Thermionic scanner pinpoints work function of emitter surfaces
In the electron tube testing, a thermionic scanner makes accurate spatial resolution measurements of the metallic surface work functions of emitters. The scanner determines the emitter function and its local departures from the mean value on a point-by-point basis for display on an oscilloscope.
Rasor, N. S.↗
Experimental measurements of the work functions and desorption energies of the systems O-W, O-Mo, O-Re, O-Ta, and Cs-O-Ta.
Thermionic work functions and desorption energies for oxygen on polycrystalline W, Mo and Re filaments, discussing oxygen pressure and filament temperature
Fehrs, D. L.↗
Work function measurements by the field emission retarding potential method.
Description of the theoretical foundation of the field electron retarding potential method, and review of its experimental application to the measurement of single crystal face work functions. The results obtained from several substrates are discussed. An interesting and useful fallout from the experimental approach described is the ability to accurately measure the elastic and inelastic reflection coefficient for impinging electrons to near zero-volt energy.
Strayer, R. W.↗
Accurate vertical ionization energy and work function determinations of liquid water and aqueous solutions
A generalised liquid-phase photoelectron spectroscopy approach is reported, allowing accurate, absolute energy scale ionisation energies of liquid water and aqueous solutions, as well as liquid water's work function to be reported.
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
Work function measurement of lanthanum-boron compounds
The relationship between emission properties and sample composition is studied for lanthanum-boron compounds. Specifically, the La-B system is considered between 1400 and 2100 K and between LaB(4.24) and LaB(29.2) to determine the phase relationship, chemical activity of the compounds, vapor composition, and vaporization rate. The results indicate that: (1) a blue-colored phase near LaB(9) exists between a purple-colored LaB(6) and elemental boron, (2) vaporization is sufficiently more rapid than diffusion so that great compositional differences exist between the surface and the interior, (3) an activation energy lowers the boron vaporization rate from LaB(6), and (4) a steady-state surface composition between LaB(6.04) and LaB(6.07) exists for freely vaporizing materials as a function of interior composition, purity, and temperature. It is noted that the ultimate life of a thermionic diode is governed by electrode vaporization rate whereas efficiency is governed by the electrode work function.
Jacobson, D. L.↗