Surface Modification of Bismuth by ALD of Antimony Oxide for Suppressing Lattice Thermal Conductivity

Abstract

Surface modification may significantly improve the performance of thermoelectric materials by suppressing thermal conductivity. Using the powder atomic layer deposition method, the newly developed Sb2O5 thin films produced from SbCl5 and H2O2 were formed on the surfaces of Bi powders. Because of the high thermal resistance generated by Sb2O5 layers on Bi particles, a substantial decrease in κ tot from 7.8 to 5.7 W m–1 K–1 was obtained with just 5 cycles of Sb2O5 layer deposition and a 16% reduction in κ lat. Because of the strong phonon scattering, the maximum zT values increased by around 12% and were relocated to 423 K.

Selective Dissolution‐Derived Nanoporous Design of Impurity‐Free Bi2Te3 Alloys with High Thermoelectric Performance

“…To enhance phonon scattering, considerable effort has been dedicated to the creation of structural defects such as heterodoping, [6][7][8][9] inclusion of a secondary phase, [10][11][12][13][14][15] dislocations, [16,17] and heterointerfaces. [7,[18][19][20][21] However, the creation of structural defects using heterogeneous elements or deviation from stoichiometry generally induces a change in electronic carrier concentration. [20] Thus, these approaches possibly affect not only phonon transport but also electronic carrier transport.…”

Improving the thermoelectric performance of ZrNi(In,Sb)-based double half-Heusler compounds

“…7 To realize effective decoupling, tremendous efforts are devoted, which can generally be categorized into two approaches. 8 One is to maximize the PF by optimizing the carrier concentration via doping or band engineering, 9 while another one targets seeking materials or processes to minimize the thermal conductivity. 10 As a prominent TE material candidate in the moderate temperature region, half-Heusler (HH) compounds have attracted signicant attention due to their low cost, high thermal stability, and mechanical robustness, as well as their excellent electrical properties.…”

“…7 To realize effective decoupling, tremendous efforts are devoted, which can generally be categorized into two approaches. 8 One is to maximize the PF by optimizing the carrier concentration via doping or band engineering, 9 while another one targets seeking materials or processes to minimize the thermal conductivity. 10…”

Unlocking the Potential of Porous Bi2Te3-Based Thermoelectrics Using Precise Interface Engineering through Atomic Layer Deposition

“…ALD, which is a thin-film growth technique based on a self-limiting mechanism, enables the conformal coating of heterogeneous thin films over thermoelectric powders. Thus, the introduction of the ALD technique allows for the creation of a core–shell structure consisting of a thermoelectric core and a heterointerface. − In particular, the use of the ALD approach for fabricating Bi 2 Te 3 -based alloys has been reported to result in grain refinement, , indicating the possibility of improving the mechanical strength of the materials. Furthermore, the heterointerfaces formed through ALD can further enhance mechanical strength by inhibiting the propagation of cracks and dislocations.…”