Ultra-low thermal conductivity in B₂O₃ composited SiGe bulk with enhanced thermoelectric performance at medium temperature region

Abstract

All-scale scattering contributes to the reduction of lattice thermal conductivity of SiGe-based TE materials and leads to a maximum ZT value of 1.47 at 873 K, which is best one in the temperature range of 300–900 K ever reported.

Thermoelectric enhancement of p-type Si 80Ge 20 alloy via co-compositing of dual oxides: Respective regulation for power factor and thermal conductivity by β-Ga 2O 3 and SiO 2 aerogel powders

“…2. Similar behavior of oxide decomposing was also observed in Y 2 O 3 -composited SiGe bulk [21] and B 2 O 3 -composited SiGe bulk [22]. There is also no XRD feature of Ga because it is extremely active, and most of them are vanished via evaporation in SPS process; only a small amount of precipitation exists at grain boundaries.…”

“…The 1-dimensional dislocation [17] and grain boundary [18,19] were demonstrated to augmentedly suppress phonons with intermediate frequency [8,9]. Furthermore, the nanoinclusion, which was formed via direct compounding [20] or in-situ precipitation [21,22], acted as consolidated suppression on the phonon with low frequencies [8,23].…”

Recent advances in interface engineering of thermoelectric nanomaterials

“…5 illustrates some of these systems' results. Nong et al 111 successfully introduced the B 2 O 3 second phase in SiGe by ball milling and spark plasma Fig. 5 Comparison of ZT values before and after doping of different oxides into different TE materials.…”

“…5 illustrates some of these systems' results. Nong et al 111 successfully introduced the B 2 O 3 second phase in SiGe by ball milling and spark plasma sintering (SPS) processes. Although the B 2 O 3 second phase boundary scattered carriers, resulting in a decrease in mobility, the increase in resistivity was acceptable.…”

Temperature dependences of thermoelectric properties of bulk SiGeAu composites

“…Silicon germanium (SiGe) has been attracted attention as one of the promising thermoelectric materials due to its non-toxicity, chemical stability, and high ZT in the high temperature range [38][39][40][41][42][43][44][45][46][47][48][49][50][51][52]. However, SiGe does not have high ZT near room temperature (RT).…”