0.3Ni 0.15Co 3.85Sb 12 skutterudite: High pressure processing technique and thermoelectric properties]]>

摘要

AbstractIn this letter, Ni substitution for Co and Ba filling into the voids were simultaneously applied to the CoSb3bulks by the high pressure and high temperature (HPHT) method. As the results, the polycrystalline Ba0.3Ni0.15Co3.85Sb12skutterudite bulks were successfully synthesized and the systematic thermoelectric properties were investigated. In our experiments, the synthesized time was sharply shortened to 30?min, which is markedly an advantage for mass production. The multiple textures and microstructures were revealed, including vortices-like structures, defects, and lattice dislocations. Remarkably, pressure tuning led to the increase of the Seebeck coefficient and electrical resistivity, yielding an optimized power factor of 11.7?×?10?4Wm?1K?2in the Ba0.3Ni0.15Co3.85Sb12sample prepared at 3?GPa?at room temperature, which yielded a 10-fold improvement in power factor and showed distinct reduction of thermal conductivity compared with pure CoSb3sample. The maximum zT value 0.91 was obtained at 700?K for Ba0.3Ni0.15Co3.85Sb12sample. The experimental results suggest that the effective elements doping combining with HPHT synthesis could optimize electrical and thermal transport properties in skutterudites.Graphical abstractDisplay OmittedHighlights?The synthesized time was sharply diminished to half an hour via the HPHT method.?The microstructures for Ba0.3Ni0.15Co3.85Sb12samples were analyzed.?With increasing pressure, the change of electrical properties was researched.?The maximum zT 0.91 of the Ba0.3Ni0.15Co3.85Sb12was obtained at 700?K.]]>