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Here, Pt current collectors were shown to dramatically increase the oxygen surface exchange coefficient ( k chem ) of Pr 0.1 Ce 0.9 O 2− x , suggesting they are likely responsible for a significant portion of the k chem variation in the literature.
Abstract We describe the results of a multi-scale, multi-physics modeling assessment of SOLPS-ITER, hPIC2, RustBCA and Xolotl, in which five single-crystal tungsten (W) samples were placed in a reciprocating collector probe and exposed to helium (He) plasma in the WEST fusion device. In our models, we considered a pure (100 %) He plasma, as well as one with oxygen (O) present (95% He 5% O) corresponding to the impurity concentration estimated during the C4 He campaign in WEST. Our SOLPS simulations approximately match experimental reciprocating Langmuir probe plasma measurements of plasma density and temperature. Using these plasma parameters as input, hPIC2 and RustBCA predict that the presence of oxygen impurities lead to a 15%–20% decrease in ion and heat fluxes to the surface, and an order of magnitude higher sputtering yields (compared with a pure He plasma). Xolotl predictions for the response of tungsten to plasma surface interactions (PSIs) agree with experimental LAMS analysis, and indicate large near-surface He concentrations, which quickly decay with depth. Our model also shows an increasing role of erosion—in removing the near-surface He—with time. Overall, slightly higher retention is predicted for tungsten exposed to a pure He plasma, with the largest differences in the near-surface gas content caused by the large oxygen-induced erosion. This highlights the important role that impurities play in PSI. Therefore, future work will focus on providing a fully self-consistent description of oxygen (and oxides, etc.) in our models, through multi-species implementation in GITR and inclusion of oxygen and tungsten oxide formation in Xolotl.
The use of three-dimensional porous nickel foam as the current collector of the nickel hydroxide electrode adds significantly to the cost of the nickel-based alkaline rechargeable batteries. Although iron is considerably less expensive than nickel, iron corrodes at the operating potential of the nickel hydroxide electrode. We have found that a 70–100 nm thick thermal coating of cobalt ferrite spinel protects the iron from corrosion. Such a coated iron substrate was found to be stable against corrosion even when polarized anodically at 10 mA cm -2 in 30% potassium hydroxide electrolyte for 1000 h. While the thermal coating of cobalt ferrite protected iron against corrosion, incorporation of lithium ions into the coating was found to enhance the electrical conductivity of the coating. XPS and EXAFS studies confirmed that the enhanced conductivity resulted from an increase in the population of Co 3+ in the ferrite spinel lattice. An inexpensive iron (steel) substrate protected by such a coating when used as a nickel hydroxide battery electrode exhibited a specific capacity of 0.25 Ah g -1 at C/5 discharge rate, comparable to a nickel hydroxide electrode based on a relatively expensive nickel foam substrate. The steel-based electrode also exhibited no noticeable degradation over 150 cycles at C/2 rate. This demonstration of a robust and economical steel substrate presents a unique opportunity for reducing the cost of the nickel hydroxide battery electrode in alkaline batteries
The pursuit of batteries capable of extreme fast charging (XFC), that also satisfy high energy and safety criteria, poses a significant challenge to current lithium-ion battery technologies. Additionally, the increasing demand for aluminum (Al) and copper (Cu) in electrification, and vehicle lightweighting is driving these metals towards near-critical status in the medium term. This study introduced metalized polymer films by depositing an Al or Cu thin layer onto two sides of a polyethylene terephthalate (PET) film – named mPET/Al and mPET/Cu, as lightweight, cost-effective alternatives to traditional metal current collectors in LIBs.
By mounting the Fresnel lens in eight steps above three paraboloidal reflector rings of epoxy resin with aluminized surfaces, a light weight, wide-aperture solar energy collector is devised.
Vapor grown silicon dioxide layer protects base-collector junction in silicon planar transistors during the emitter diffusion process. This oxide fills in any imperfections that exist in the thermally grown oxide layer and is of greater thickness than that layer. This process is used to deposit protective silicon dioxide coatings on optical surfaces.
Manometric gauge with outside collector for very low pressure applications
Niobium and nickel as thermionic converter collector materials, comparing characteristics
Pairs of emitter and collector sheaths for cesium thermionic diodes
Current-voltage characteristics of variable spaced thermionic converter with tungsten emitter and niobium collector
Emitter and collector sheaths for cesium thermionic diodes with polycrystalline tungsten electrodes
Characteristics of thermionic converter with chloride vapor deposited tungsten emitter and nickel collector
Integrated circuit with multiple collector current source achieves the equivalent of a large number of resistors in a small area. Functional equivalents of a transistor reduce the size requirement for low power integrated circuits, providing an efficient alternative to the conventional diffused resistor process in integrated circuit fabrication.
Thermionic coverter with chloride vapor deposited tungsten emitter and nickel collector
Fixed space planar thermionic diode with collector guard ring for studying various emitter materials, measuring emitter temperatures
Bent beam ionization gage linearity from calibrated nude Modulated Bayard-Alpert /MBA/ gage, discussing buried collector and tabulated magnetron gages
Thermionic converter operation with 112 to 114 oriented tungsten emitter and niobium collector with oxygen
Performance characteristics of parallel plane, variable spaced thermionic converter with tungsten emitter and molybdenum-niobium collector