Thermoelectric atomization

Two thermocouples, Em at x = 0 and Ex at a distance x, permit the monitoring of the atomic hydrogen concentration change along the side-tube. The atoms recombining on the thermocouple tip covered by the active catalyst evolve the heat of reaction and thus the thermoelectric power becomes a relative measure of the concentration of atoms in the gas phase. Finally, one obtains for the direct use in an experimental work the following equation... 

The silver white, shiny, metal-like semiconductor is considered a semimetal. The atomic weight is greater than that of the following neighbor (iodine), because tellurium isotopes are neutron-rich (compare Ar/K). Its main use is in alloys, as the addition of small amounts considerably improves properties such as hardness and corrosion resistance. New applications of tellurium include optoelectronics (lasers), electrical resistors, thermoelectric elements (a current gives rise to a temperature gradient), photocopier drums, infrared cameras, and solar cells. Tellurium accelerates the vulcanization of rubber. 

C. Shannon, A. Gichuhi, P. A. Barnes, and M. J. Bozack, Electrosynthesis of thermoelectric materials by electrochemical atomic layer epitaxy a prelimnary investigation, Seattle, Washington, 1999, pp 282. 

The transition-metal monopnictides MPn with the MnP-type structure discussed above contain strong M-M and weak Pn-Pn bonds. Compounds richer in Pn can also be examined by XPS, such as the binary skutterudites MPn , (M = Co, Rh, Ir Pn = P, As, Sb), which contain strong Pn-Pn bonds but no M-M bonds [79,80], The cubic crystal structure consists of a network of comer-sharing M-centred octa-hedra, which are tilted to form nearly square Pnn rings creating large dodecahedral voids [81]. These voids can be filled with rare-earth atoms to form ternary variants REM Pnn (RE = rare earth M = Fe, Ru, Os Pn = P, As, Sb) (Fig. 26) [81,82], the antimonides being of interest as thermoelectric materials [83]. 

Figure 6. Thermoelectric power coefficient as a function of H atoms/LaNi5 for hydrogen charged LaNij at room temperature (green) and 190°C (blue).15...

A second historical line which, is of paramount importance to the present understanding of solid state processes is concerned with electronic particles (defects) rather than with atomic particles (defects). Let us therefore sketch briefly the, history of semiconductors [see H. J, Welker (1979)]. Although, the term semiconductor was coined in 1911 [J. KOnigsberger, J, Weiss (1911)], the thermoelectric effect had already been discovered almost one century earlier [T. J. Seebeck (1822)], It was found that PbS and ZnSb exhibited temperature-dependent thermopowers, and from todays state of knowledge use had been made of n-type and p-type semiconductors. Faraday and Hittorf found negative temperature coefficients for the electrical conductivities of AgzS and Se. In 1873, the decrease in the resistance of Se when irradiated by visible light was reported [W. Smith (1873) L. Sale (1873)]. It was also... 

Finally, a very simple molecular electronic component is benzene-1,4-dithiol, which is readily used as a linker between gold electrodes in the same way as the cobalt terpyridine complex shown in Figure 11.40. Benzene dithiol has been used to demonstrate the thermoelectric effect in molecular electronic systems as a linker between a gold surface and the gold tip of a modified atomic force microscope. Thermoelectricity (termed the Seebeck effect) is the generation of an electrical potential... 

Brian C. Sales, David G. Mandrus, and Bryan C. Chakoumakos, Use of Atomic Displacement Parameters in Thermoelectric Materials Research... 

Figure 4.49. Unit cell of Bi2Te3 - a widely studied thermoelectric material. The blue atoms are Bi, and the pink atoms are Te. Reproduced with permission from Tritt, T. M. Subramanian, M. A. MRS Bull. 2006, 31, 188. Copyright 2006 Materials Research Society.

The electrical properties of active carbon (e.g., conductivity, thermoelectric power, work function) are directly related to the material structure. Precursor materials usually containing only a-bonds between carbon atoms in the sp state are generally insulators (conductivity less than 10" itT ). When 7t-bonds... 

Use Photoelectric cells, getter in vacuum tubes, hydrogenation catalyst, ion propulsion systems, plasma for thermoelectric conversion, atomic clocks, rocket propellant, heat-transfer fluid in power generators, thermochemical reactions, seeding combustion gases for magnetohydrodynamic generators. 

The thermoelectric properties of doped and sintered samples are presented in Table 1. The electrical resistivity of the composite made by those doped powders become very high, compared to monolithic phases. So far, we consider the results to have been caused by Ge diffusion between SiGe/ PbTe interface. By EPMA analysis, 0.9-3.5at% of Ge were probed in PbTe phase. After the experimental work by T.Abakumowa [12] such Ge atoms could work as donor site in PbTe lattice. 

Bi2Te3-based compounds are well known to be good thermoelectric materials for the applications near room temperature. The crystal structure of Bi2Te3 at room temperature is rhombohedral (a=0.438 nm and c=3.049 nm) [1]. This crystal is composed of atomic layers in the order of Te/Bi/Te/Te/... 

ELECTROSYNTHESIS OF THERMOELECTRIC MATERIALS BY ELECTROCHEMICAL ATOMIC LAYER EPITAXY A PRELIMINARY INVESTIGATION... 

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