Low-cost fabrication of high efficiency solid-state neutron detectors

Author(s):  
Jia-Woei Wu ◽  
Kuan-Chih Huang ◽  
Adam Weltz ◽  
Erik English ◽  
Mona M. Hella ◽  
...  
2005 ◽  
Author(s):  
R. J. Nikolic ◽  
C. L. Cheung ◽  
C. E. Reinhardt ◽  
T. F. Wang

2012 ◽  
Vol 7 (03) ◽  
pp. C03014-C03014 ◽  
Author(s):  
Y Danon ◽  
J Clinton ◽  
K C Huang ◽  
N LiCausi ◽  
R Dahal ◽  
...  

2014 ◽  
Vol 2014 ◽  
pp. 1-3
Author(s):  
Ray-Hua Horng ◽  
Kei May Lau ◽  
Hao-Chung Kuo ◽  
Nelson Tansu

MRS Bulletin ◽  
1989 ◽  
Vol 14 (9) ◽  
pp. 18-21
Author(s):  
Robert A. Huggins

This issue of the MRS BULLETIN contains three articles relating to the general field that has come to be known as Solid State Ionics. The central feature of this area of science and emerging technology is the rapid transport of atomic or ionic species within solids, and the various phenomena, of both scientific and technological interest, that are related to it.Attention to this area has grown greatly in recent years because of the rapidly increasing recognition of the possibility of a wide range of interesting technological applications. One example already widespread is the use of an oxygen-conducting solid electrolyte as the critical element in the oxygen sensors installed in the exhaust systems of almost all current automobiles to reduce deleterious emissions and improve the efficiency of the combustion process.Work is under way in a number of other directions, including static and dynamic chemical sensors, solid state electrochemical reactors, low impedance selective atomic filters, new concepts for the direct conversion of heat to electricity by the use of sodium- or hydrogen-transporting cycles, a novel method for the low cost electrolysis of water at intermediate temperatures, batteries that can store greatly increased amounts of energy, ion exchange materials, solid state laser hosts, high efficiency fuel cells, electrochromic materials and configurations for both optical displays and “smart windows,” advanced catalysts, atomic reservoirs and pumps, high temperature superconductors, and possibly solid state fusion hosts.Despite this recent attention, however, it is worth noting that interest in solids in which ionic species can move with unusual rapidity is actually not new at all. As early as 1839, Michael Faraday reported measurements on several materials that showed an unusual increase in electrical conductivity at elevated temperatures, contrary to that found in normal metals.


Author(s):  
K.M. Hones ◽  
P. Sheldon ◽  
B.G. Yacobi ◽  
A. Mason

There is increasing interest in growing epitaxial GaAs on Si substrates. Such a device structure would allow low-cost substrates to be used for high-efficiency cascade- junction solar cells. However, high-defect densities may result from the large lattice mismatch (∼4%) between the GaAs epilayer and the silicon substrate. These defects can act as nonradiative recombination centers that can degrade the optical and electrical properties of the epitaxially grown GaAs. For this reason, it is important to optimize epilayer growth conditions in order to minimize resulting dislocation densities. The purpose of this paper is to provide an indication of the quality of the epitaxially grown GaAs layers by using transmission electron microscopy (TEM) to examine dislocation type and density as a function of various growth conditions. In this study an intermediate Ge layer was used to avoid nucleation difficulties observed for GaAs growth directly on Si substrates. GaAs/Ge epilayers were grown by molecular beam epitaxy (MBE) on Si substrates in a manner similar to that described previously.


Author(s):  
P. G. Kotula ◽  
D. D. Erickson ◽  
C. B. Carter

High-resolution field-emission-gun scanning electron microscopy (FESEM) has recently emerged as an extremely powerful method for characterizing the micro- or nanostructure of materials. The development of high efficiency backscattered-electron detectors has increased the resolution attainable with backscattered-electrons to almost that attainable with secondary-electrons. This increased resolution allows backscattered-electron imaging to be utilized to study materials once possible only by TEM. In addition to providing quantitative information, such as critical dimensions, SEM is more statistically representative. That is, the amount of material that can be sampled with SEM for a given measurement is many orders of magnitude greater than that with TEM.In the present work, a Hitachi S-900 FESEM (operating at 5kV) equipped with a high-resolution backscattered electron detector, has been used to study the α-Fe2O3 enhanced or seeded solid-state phase transformations of sol-gel alumina and solid-state reactions in the NiO/α-Al2O3 system. In both cases, a thin-film cross-section approach has been developed to facilitate the investigation. Specifically, the FESEM allows transformed- or reaction-layer thicknesses along interfaces that are millimeters in length to be measured with a resolution of better than 10nm.


2019 ◽  
Author(s):  
Charlys Bezerra ◽  
Géssica Santos ◽  
Marilia Pupo ◽  
Maria Gomes ◽  
Ronaldo Silva ◽  
...  

<p>Electrochemical oxidation processes are promising solutions for wastewater treatment due to their high efficiency, easy control and versatility. Mixed metal oxides (MMO) anodes are particularly attractive due to their low cost and specific catalytic properties. Here, we propose an innovative thermal decomposition methodology using <a>polyvinyl alcohol (PVA)</a> as a solvent to prepare Ti/RuO<sub>2</sub>–IrO<sub>2</sub> anodes. Comparative anodes were prepared by conventional method employing a polymeric precursor solvent (Pechini method). The calcination temperatures studied were 300, 400 and 500 °C. The physical characterisation of all materials was performed by X-ray diffraction and scanning electron microscopy coupled with energy dispersive spectroscopy, while electrochemical characterisation was done by cyclic voltammetry, accelerated service lifetime and electrochemical impedance spectroscopy. Both RuO<sub>2</sub> and IrO<sub>2</sub> have rutile-type structures for all anodes. Rougher and more compact surfaces are formed for the anodes prepared using PVA. Amongst temperatures studied, 300 °C using PVA as solvent is the most suitable one to produce anodes with expressive increase in voltammetric charge (250%) and accelerated service lifetime (4.3 times longer) besides reducing charge-transfer resistance (8 times lower). Moreover, the electrocatalytic activity of the anodes synthesised with PVA toward the Reactive Blue 21 dye removal in chloride medium (100 % in 30 min) is higher than that prepared by Pechini method (60 min). Additionally, the removal total organic carbon point out improved mineralisation potential of PVA anodes. Finally, this study reports a novel methodology using PVA as solvent to synthesise Ti/RuO<sub>2</sub>–IrO<sub>2</sub> anodes with improved properties that can be further extended to synthesise other MMO compositions.</p>


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