Thermoelectric performance of silicon with oxide nanoinclusions

Abstract

Silicon nanoparticles produced via a plasma-based technique have been sintered into bulk nanostructured samples. These samples have micron-sized crystalline domains and contain well-dispersed oxide nanoinclusions. We have compared the thermoelectric performance of such structure to that of a control sample produced by sintering ball-milled silicon powders. The control sample has lower precipitate density and is composed of nanograins. Despite the stark difference in nanostructure, both samples have comparable thermal conductivity, and the sample with nanoinclusions has higher power factor and ZT. This result confirms that grain size engineering is not the only promising route to achieving improved thermoelectric performance. (Figure Presented) IMPACT STATEMENT: By controlling the feedstock powder processing technique, it is possible to obtain well-dispersed nanoinclusions in sintered bulk samples. These are as effective at reducing thermal transport properties as grain boundaries.