Bi(2-x)SbxTe3 Thermoelectric Composites with High Average zT Values: From Materials to Devices

Abstract

(Bi,Sb)Te-based materials have drawn extensive attention for nearly two centuries as one of the most successful commercial thermoelectric (TE) materials. However, Bi(2-x)SbxTe3 composites with remarkable average figure of merit (zTavg) values are highly desired in terms of the great contribution on expanding the applying temperature ranges of the commercial devices. Herein, Bi0.35Sb1.65Te3 compound with outstanding zTavg value of about 1.18 (integrate from 298 to 498 K) was obtained via delaying the bipolar effect by precipitating multi-scale Sb2Te3 inclusions. The power factor (PF) was enhanced from 2.1×10−3 Wm−1 K−2 (Bi0.5Sb1.5Te3) to 4.3×10−3 Wm−1 K−2 (Bi0.35Sb1.65Te3) by optimizing the carrier concentration from 1.9×1019 cm−3 to 3.9×1019 cm−3 via adjusting the proportions of Bi:Sb. Correspondingly, the lattice thermal conductivities (kl) were distinctly suppressed by the additional multiple phonon scattering resulting from the Sb2Te3 precipitates. Consequently, a remarkable zTmax, as high as ~1.35 at 373 K was obtained in the Bi0.35Sb1.65Te3 sample. The temperature difference ( T, 6.0 A current) of the TE device that assembled with the commercial N-type Bi(Te,Se) ingot has reached up to 66.9 K. The high zTavg, zTmax and T values will further promote the commercial applications of (Bi,Sb)Te-based materials in a wide temperature range.

Research Progress of Interfacial Design between Thermoelectric Materials and Electrode Materials

“…Bi 2 Te 3 -based alloys were first investigated as promising thermoelectric materials in the 1960s, and so far they are still the most popular near-room-temperature thermoelectric materials. − In the past few decades, great improvement in thermoelectric performance has been achieved in p-type Bi 2 Te 3 . A maximum ZT of ∼2.4 for a p-type Bi 2 Te 3 superlattice thin film has been reached by controlling the transport of phonons and electrons .…”

Conductive Polymer Coated Layered Double Hydroxide as a Novel Sulfur Reservoir for Flexible Lithium‐Sulfur Batteries

“…[21][22][23] However, carbon-based materials with the non-polar feature cannot fully suppress the "shuttle effect" of the polar LiPSs, witnessing slow dissolution in electrolytes. [24][25] Compared with carbonbased materials, the appealing features of conductive polymers, such as polypyrrole (PPy), polyaniline (PANI), poly(p-phenylene sulfide) (PPS), and poly(3,4-ethylene dioxythiophene) (PEDOT), have shown similar electronic conductivity but possessed polar functional groups (CN, CS, CO) and conjugated structures Lithium-sulfur battery (LSB) is widely regarded as the most promising nextgeneration energy storage system owing to its high theoretical capacity and low cost. However, the practical application of LSBs is mainly hampered by the low electronic conductivity of the sulfur cathode and the notorious "shuttle effect", which lead to high voltage polarization, severe over-charge behavior, and rapid capacity decay.…”

Synthesis of SnSe1–xSx Polycrystals with Enhanced Thermoelectric Properties Via Hydrothermal Methods Combined with Spark Plasma Sintering

“…Thermoelectric (TE) materials are regarded as the most promising new clean energy sources, which can effectively ameliorate the greenhouse effect and the earth’s environment. − The conversion between heat energy and electric energy can be realized directly through thermoelectric materials , that do not release any hazardous gaseous chemical residues. , The thermoelectric component is a mechanically reliable, stable environment of the electric device, with no operating mechanical vibration and noise. , To apply thermoelectric materials in the future, the key problem is improving the conversion efficiency. The thermoelectric properties are determined by a dimensionless figure of merit ( ZT ), which is defined as ZT = S 2 σ T /κ t , where S is the Seebeck coefficient, σ is the electrical conductivity, S 2 σ is the power factor (PF), T is the absolute temperature, and κ t is the total thermal conductivity, which consists of the lattice thermal conductivity (κ l ) and the electron thermal conductivity (κ e ) …”