High‐Sensitivity Flexible Thermocouple Sensor Arrays Via Printing and Photonic Curing

Abstract Despite remarkable advances, high‐performance thermoelectric (TE) materials‐based thermocouples (TCs) lack mechanical robustness and flexibility. Hence, conventional low Seebeck coefficient metals (Ni, Cu, Fe) wire‐junction‐based TCs are used for temperature sensor applications. However, not only the sensitivity of the metal‐based TC sensor is low, but also it is very difficult to fabricate a pixelated sensor using the conventional approach. In this study, high‐performance (SbBi) 2 (TeSe) 3 ‐based printed flexible TE materials are employed to fabricate two types of shape‐conformable TC‐based temperature sensor arrays with 25 pixels (TSA I and TSA II). Bi 0.5 Sb 1.5 Te 3 ‐based p‐type (p‐BST) printed TE film and copper are used to fabricate TSA I, and the p‐type film together with the Bi 2 Te 2.7 Se 0.3 ‐based n‐type (n‐BT) film is used to fabricate TSA II. A high average sensitivity (S exp ) value of ≈124 µV °C −1 for TSA I and ≈319 µV °C −1 for TSA II is attained with high linearity.