熔体旋甩法制备p型填充式方钴矿化合物Ce0.3Fe1.5Co2.5Sb12的微结构及热电性能

采用熔体旋甩法结合放电等离子烧结技术(MS-SPS)制备了p型填充式方钴矿化合物Ce_0.3Fe_1.5Co_2.5Sb₁₂,研究了熔体旋甩工艺对微结构以及热电性能的影响规律.结果表明,较高的铜辊转速和较低的喷气压力有利于提高熔体的冷却速率,使带状产物晶粒细化.薄带经SPS烧结后得到致密、基本单相、晶粒尺寸均匀细小(150—300 nm)的块体.与传统方法制备的试样相比,MS-SPS试样虽然电导率有所降低,但因具有较大的Se 关键词： 熔体旋甩 p型填充式方钴矿化合物 微结构 热电性能

Microstructure and themoelectric properties of p-type filled skutterudite Ce0.3 Fe1. 5 Co2. 5 Sb12 prepared by melt-spinning method

Polycrystalline nanostructured bulk samples of p-type filled skutterudite Ce_0.3Fe_1.5Co_2.5Sb₁₂ have been prepared by melt-spinning (MS) method combined with spark plasma sintering (SPS). The effects of melt-spinning process on their microstructure and thermoelectric properties have been investigated. The results indicate that the ribbons have finer microstructure with the increasing cooling rate for melt-spun ribbons, resulting from the increasing copper wheel speed and decreasing ejection pressure. Compared with the sample prepared by traditional method, the samples prepared by MS-SPS method have higher power, factor due to the enhanced thermopower, despite the slightly reduced electrical conductivity. Meanwhile, the lattice thermal conductivity of the MS-SPS samples is significantly suppressed. Hence, the thermoelectric performance of the MS-SPS samples is greatly improved, and the figures of merit reach about 0.55 at 750 K.