Realizing High Thermoelectric Performance of Bi-Sb-Te-Based Printed Films through Grain Interface Modification by an In Situ-Grown β-Cu2-δSe Phase

Md Mofasser Mallick; Leonard Franke; Andres Georg Rösch; Sarfraz Ahmad; Holger Geßwein; Yolita M Eggeler; Magnus Rohde; Uli Lemmer

doi:10.1021/acsami.1c13526

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

ACS Appl Mater Interfaces. 2021 Dec 29;13(51):61386-61395. doi: 10.1021/acsami.1c13526. Epub 2021 Dec 15.

Authors

Md Mofasser Mallick¹, Leonard Franke¹, Andres Georg Rösch¹, Sarfraz Ahmad², Holger Geßwein², Yolita M Eggeler³, Magnus Rohde², Uli Lemmer^{1

4}

Affiliations

¹ Light Technology Institute, Karlsruhe Institute of Technology, 76131 Karlsruhe, Germany.
² Institute for Applied Materials Karlsruhe Institute of Technology, Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen, Germany.
³ Laboratory for electron microscopy, Karlsruhe Institute of Technology, 76131 Karlsruhe, Germany.
⁴ Institute of Microstructure Technology Karlsruhe Institute of Technology, Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen, Germany.

PMID: 34910878
DOI: 10.1021/acsami.1c13526

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_0.5Sb_1.5Te₃-based printable TE materials have been advanced by interface modification of the TE grains with a nonstoichiometric β-Cu_2-δSe-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.

Keywords: Bi-Sb-Te alloy; Cu2Se; high ZT; printed TEGs; printed thermoelectrics.