Realizing High Thermoelectric Performance of Bi-Sb-Te-Based Printed Films through Grain Interface Modification by an In Situ-Grown β-Cu_2-δSe Phase

Abstract

It has been a substantial challenge to develop a printed thermoelectric (TE) material with a figure-of-merit ZT > 1. In this work, high ZT p-type Bi 0.5 Sb 1.5 Te 3 -based printable TE materials have been advanced by interface modification of the TE grains with a nonstoichiometric β-Cu 2-δ Se-based inorganic binder (IB) through a facile printing−sintering process. As a result, a very high TE power factor of ∼17.5 μW cm −1 K −2 for a p-type printed material is attained in the optimized compounds at room temperature (RT). In addition, a high ZT of ∼1.2 at RT and of ∼1.55 at 360 K is realized using thermal conductivity (κ) of a pellet made of the prepared printable material containing 10 wt % of IB. Using the same material for p-type TE legs and silver paste for n-type TE legs, a printed TE generator (print-TEG) of four thermocouples has been fabricated for demonstration. An open-circuit voltage (V OC ) of 14 mV and a maximum power output (P max ) of 1.7 μW are achieved for ΔT = 40 K for the print-TEG.

Photonic Curing Enables Ultrarapid Processing of Highly Conducting β-Cu2−δSe Printed Thermoelectric Films in Less Than 10 ms

“…Nevertheless, there is a trade-off between high performance and good flexibility in the films. 19 − 21 We have also reported high-performance Ag 2 Se-based printed n-type TE films prepared by a similar sintering process. 13 , 22 , 23 In this work, we have employed a fast photonic-curing technology on printed Cu–Se-based films to address the drawbacks associated with the traditional procedure to fabricate flexible β-Cu 2−δ Se-based TE films.…”

“…Recently, we have reported Sb–Bi–Te/β-Cu 2−δ Se TE films prepared by sintering in a vacuum oven. Nevertheless, there is a trade-off between high performance and good flexibility in the films. − We have also reported high-performance Ag 2 Se-based printed n-type TE films prepared by a similar sintering process. ,, In this work, we have employed a fast photonic-curing technology on printed Cu–Se-based films to address the drawbacks associated with the traditional procedure to fabricate flexible β-Cu 2−δ Se-based TE films. We have used screen printing to fabricate TE films with high spatial resolution, and a very fast photonic-curing process is implemented to sinter the films.…”

Inorganic‐Based Printed Thermoelectric Materials and Devices

“…The reported PF is around 1.750 Â 10 3 μW m À1 K À2 . [127] Apart from these, there are other reports where AgS-based ink doped with Te and Se showed good mechanical properties [128,129] and high ZT value up to 0.44 at 300 K making them good candidates for flexible TE applications. [130,131] Table 1 can be referred to as a summary of the PFs and the ZT values of recently reported inorganic-based printed TE materials.…”

Endotaxial Intergrowth of Copper Telluride in GeTe-Rich Germanium Antimony Tellurides Leads to High Thermoelectric Performance

“…Typical PLEC materials, 29 Cu-containing or Cu-doped chalcogenides, like PbSe:Cu, 30 Bi 2 Te 3 :Cu, 31 Bi 2 Te 2.7 Se 0.3 :Cu, 32 or CuPb 18 SbTe 20 with nano-Ag/Cu joints, 33 as well as thermoelectric composite materials, like PbTe-Cu 2 Te, 34 Bi 2 Te 3 /CuI/Sn, 35 or Bi-Sb-Te with β-Cu 2−δ Se, 36 as an effective dopant to optimize the carrier concentration by effectively suppressing whole carriers at a low overall impurity concentration. 37 (Co-)doping with Cu + Ti + In + Pb, 38 Cu + Bi/Sb, 39 Cu + BiTe, 40 Cu + Bi, 41 and Cu + Sb 42−44 has similar effects on the whole carrier concentrations and in some cases formation of Cu 2−x Te or Cu 2 GeTe 3 has been mentioned.…”

“…Typical PLEC materials, Cu-containing or Cu-doped chalcogenides, like PbSe:Cu, Bi 2 Te 3 :Cu, Bi 2 Te 2.7 Se 0.3 :Cu, or CuPb 18 SbTe 20 with nano-Ag/Cu joints, as well as thermoelectric composite materials, like PbTe-Cu 2 Te, Bi 2 Te 3 /CuI/Sn, or Bi-Sb-Te with β-Cu 2−δ Se, are an expanding field of research, especially due to the abundance and nontoxicity of copper. Also in GeTe, Cu 2 Te was realized as an effective dopant to optimize the carrier concentration by effectively suppressing whole carriers at a low overall impurity concentration .…”