Thermoelectric properties of medium-entropy PbSbTeSe alloy prepared by reactive spark plasma sintering

High-entropy materials for thermoelectric applications: towards performance and reliability

“…249 Yang et al 250 have studied the same (Ag, Sb, Sn) (S, Se, Te) system but having different stoichiometries, and the obtained k was remarkably low, measuring only 1.27 W m À1 K À1 at 300 K for the (Ag 0.15 Sb 0.15 Sn 0.7 ) (S 0.15 Se 0.15 Te 0.7 ) HEM resulting in a maximum ZT of 1.02 at 850 K. For the HEMC (Ag, Pb, Bi)(S, Se, Te) system, Yamashita et al 251 applied the entropy-driven concept and the reported properties were an ultra-low lattice k of 0.46 W m À1 K À1 and a maximum PF of 4.4 mW cm À1 K À2 both at 723 K, which induced a ZT of 0.54 at 723 K for the Ag 0.25 Pb 0.50 Bi 0.25 S 0.40 Se 0.50 Te 0.10 HEM. Yaprintseva et al 252 synthesized a single-phase (Bi 2/3 Sb 1/3 ) 2 (Te 2/5 Se 2/5 S 1/5 ) 3 HEM through a multi-step process and the obtained ZT was found to be 0.3 at 570 K. The same group studied the TE properties of the HE Bi-Sb-Te-Se-S system and the obtained maximum ZT was 0.18 at 475 K for the Bi 1.5 Sb 0.5 -Te 1.25 Se 1.25 S 0.5 HEM. 253 They have also investigated a singlephase PbSbTeSe with a ZT of 0.43 730 K, but the latter is classified as a medium-entropy material.…”

“…253 They have also investigated a single-phase PbSbTeSe with a ZT of 0.43 730 K, but the latter is classified as a medium-entropy material. 254 Deng et al 247 studied the TE properties of the (Ge, Sn, Pb)(S, Se, Te) HE system. The measured TE properties of a 2% Na-doped Ge 1/3 Sn 1/3 Pb 1/3 S 1/3 Se 1/3 Te 1/3 HEM are approximately 200 μV K −1 for α and 0.75 W cm −1 K −1 for k both at 600 K. Samanta et al 255 applied the entropy-driven concept on GeTe-based materials where they reported a high ZT of 1.8 at 660 K for the (GeTe) 80 (AgSbSe 2 ) 20 HEM.…”

Topological insulator behavior in low-temperature electrical resistivity of the high-entropy single-crystalline thick-filmed (Bi2/3Sb1/3)2 (Te2/5Se2/5S1/5)3 alloy

“…The aim of this work is to find features in the electrical resistivity of high-entropy single-crystalline (Bi 2/3 Sb 1/3 ) 2 (Te 2/5 Se 2/5 S 1/5 ) 3 alloy, prepared as a thick film, which can be attributed to specific properties of topological insulators. Developing high-entropy and medium-entropy alloys is known to be effective approach in modern materials science that allows improving the properties of structural and functional materials in desired manner [29][30][31][32][33][34][35][36]. High-entropy alloys consist of five or more principal elements taken in equimolar or near-equimolar ratios.…”

Synthesis of Ti-Cu Multiphase Alloy by Spark Plasma Sintering: Mechanical and Corrosion Properties

“…The latter method makes it possible to produce compounds of almost any metallic composition [1,23,24]. The established advantages of SPS over traditional technologies are as follows: (a) low sintering temperatures, (b) short sintering cycle times (minutes), (c) low power consumption (about 1/5 of HP), (d) uniform heating of the material, (e) control of the temperature gradient, (f) absence of sintering additives and plasticizers, (g) sintering of powders with a wide particle size distribution, (h) achieving maximum density of the material (up to 100% of theoretical), (i) one-stage sintering, and (j) cleaning of the particle surface under the influence of current.…”