Characterization of n-type bismuth-tellurium-selenium and p-type bismuth-antimony-tellurium ternary like semiconductors fabricated by shock-waved (explosive) consolidation
Abstract
Powder mixtures of Bi-Te-Se and Bi-Te-Sb were prepared by explosive consolidation to form ternary like n-type and p-type doped Bi 2Te3 thermoelectric materials. Shock-wave monoliths were compared with their corresponding conventional melt-grown n-type and p-type thermoelectric materials. The elemental powder diameters ranged from 40 μm to 3 μm. Vickers microindentation hardnesses of elemental Bi and Te particles were 0.18 and 0.56 GPa respectively. In contrast, the average of microindentation hardness in the shocked monoliths were 1.15GPa for the n-type and 1.31 GPa for the p-type material; compared to 0.72 and 0.68 GPa for the melt-grown n-type and p-type materials respectively. Elemental powders, powder mixtures, shock-wave consolidated monoliths and conventional melt-grown materials were characterized by X-ray Diffraction, Optical Microscopy, Scanning Electron Microscopy with EDS analysis and Transmission Electron Microscopy. The melt-grown materials had measured thermoelectric parameters considerably in excess of the shock-wave consolidated monoliths. Notable shock microstructures were characterized as deformation twins, while the melt-grown materials contained considerable, fine eutectic microstructures. These microstructures do not appear to be conducive to thermoelectric figure of merit optimization.
Subject Area
Metallurgy|Materials science
Recommended Citation
Munoz Estrada, Vianett Berenice, "Characterization of n-type bismuth-tellurium-selenium and p-type bismuth-antimony-tellurium ternary like semiconductors fabricated by shock-waved (explosive) consolidation" (2007). ETD Collection for University of Texas, El Paso. AAI1452588.
https://scholarworks.utep.edu/dissertations/AAI1452588