| |
[摘要]：The characterization and understanding of the presence of nanostructuring in bulk thermoelectric materials requires real space atomic level information. We report electron diffraction and high-resolution transmission electron microscopy studies of crystals of the system AgPb18SbSe20 (= 18PbSe + AgSbSe2) which reveal that this system is nanostructured rather than a solid solution. Nanocrystals or varying sizes are found, endotaxially grown in the matrix of PbSe (phase A). and consist or two phases, a cubic one (phase B) and a tetragonal one (phase C). Well-defined coherent interfaces between the phases in the same nanocrystals are observed. On the basis or the results of combined electron crystallography techniques, we propose reasonable structural models for the phases B and C. There are significant differences in the nanostructuring chemistry between AgPb18SbSe20 and the telluride analog AgPb18SbTe20 (LAST-18). |
|
