Cebixtm Cerium Hexaboride

PRODUCT INFORMATION: Cerium Hexaboride CeBixtm For years, LaB6 has been the industry standard thermionic emission cathode material. APTech has a material, CeBixTM (Cerium Hexaboride) that can be used as a direct TM replacement for LaB6. CeBix has several advantages over LaB6 cathodes, including, longer lifetime, faster start-up, lower work function, higher brightness, lower evaporation rate and the capability to recover from Contaminates. CeBixTM cathodes are a simple, direct replacement for LaB6 cathodes in nearly every instrument currently using LaB6. TM CeBix has a significantly lower evaporation rate under certain conditions than LaB6. Studies TM have shown that the material loss rate for LaB6 is almost 75% greater than that of CeBix at 1750 K in a vacuum of 2 x 10-8 torr.Thus, CeBixTM can be expected to last 30-75% longer than a LaB6 cathode when operated under proper vacuum and temperature conditions. In some applications, carbon contamination from pumping oils, solvents, or samples can effect the surface properties of LaB6 cathodes, resulting in severely decreased electron emission. In a case of mild contamination, the operator is often unaware of the problem and only sees that it is necessary to increase the cathode heating current in order to maintain emission current. This increase in cathode temperature results in shortened lifetime. In the case of severe contamination, the emission current may be completely lost. 1600 NE Miller Street McMinnville, Oregon 97128 U.S.A. Phone: 503-434-5550 Fax: 503-434-1312 Email: [email protected] Web: a-p-tech.com Evaporation Rates for LaB6 and CeB6 TM 1000 CeBix cathodes are also effected by carbon contamination, but this contamination is removed by thermal 10) - 100 desorption at normal operating temperatures. If there is a carbon bearing gas in the system, it LaB6 10 will not adhere to the cathode Evap. Rate (g/cm2 sec 10 (g/cm2 x Rate Evap. surface at operating temperature; CeB6 therefore it will not harm the TM 1 CeBix cathode. 1700 1750 1800 1850 1900 Temperature (K) A comparison of electron characteristics of LaB6, CeBixTM, and Tungsten at typical operating temperatures. CeB6 LaB6 Tungsten Filament Brightness ( A/cm2-sr) 107 107 106 Short-term beam <1 <1 <1 current stability (%RMS) Typical service life (hr) 1,500 + 1000 100 Work funtion (eV) 2.65 2.80 4.5 Operating vacuum 10-7 10-7 10-5 (torr) Evaporation rate 2.1 x 10-9 2.9 x 10-9 NA (g/cm2-sec) Give CeBixTM a try! For more information check out our website www.a-p-tech.com.

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Electrochemical Synthesis of Ceb6 Nanotubes
Journal of Materials Science and Chemical Engineering, 2014, 2, 57-62 Published Online January 2014 (http://www.scirp.org/journal/msce) http://dx.doi.org/10.4236/msce.2014.210010 Electrochemical Synthesis of CeB6 Nanotubes H. B. Kushkhov, M. K. Vindizheva, R. A. Mukozheva, A. H. Abazova, M. R. Tlenkopachev Kabardino-Balkar State University, Nalchik, Russia Email: [email protected], [email protected] Received November 2013 ABSTRACT This work presents the results of joint electroreduction of tetrafluorborate and cerium-ions, and determines the conditions of electrochemical synthesis of cerium borides in KCl-NaCl melts at the 973 K on tungsten electrode by the linear and cyclic voltammetry. Based on the current-voltage studies the optimal modes of cerium boride electrodeposition were found. KEYWORDS Molten Chloride; Linear and Cyclic Voltammetry; Cerium Borides; High Temperature Electrosynthesis; Nanotubes 1. Introduction and viscosity of the bath. Temperature electrolysis mix- ture was 1223 K - 1273 K, the voltage on the bath was Borides of rare earth metals (REM) are widely used in 3.0 - 15.0 V, current density was 0.3 - 3.0 A/cm2. The various fields of modern technology. The electrochemi- composition of the bath for cerium hexaboride obtaining cal synthesis of rare-earth borides at moderate tempera- was: CeO2 + 2B2O3 + CeF3. tures (973 - 1023 K) is a cost-effective alternative to the As noted in work [3], the obtaining of the individual direct solution-phase synthesis. The increased interest in boride phase is practically impossible or very difficult. the development of new efficient methods of producing The disadvantages are also high temperature of synthesis rare earth borides are due to remarkable properties of and complexity of the product separation from the mol- these materials, such as chemical inertness, heat resis- ten electrolyte due to the low solubility of borates and tance, a wide range of electrochemical and magnetic pro- fluoride, contamination by-products, such as borates.
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