Ultra-flexibleβ-Cu2-δSe-based p-type printed thermoelectric films

Flexibility in a printed thermoelectric (TE) material is vital for low-cost manufacturing of shape conformable TE devices. In this work, a one-pot facile method was adapted to prepare a Cu-Se-based printable ink. The ink was printed on flexible substrates followed by sintering to let beta-Cu2-delta Se phase be formed. The film is found to be exceptionally flexible with a change in film resistance < 30 % after 100 bending cycles. The performance of the flexible film then was enhanced by substituting S acute accent e' with S acute accent '. At room temperature (RT), a power factor of 250 mu Wm(-1)K(-2) with a thermal conductivity kappa of 0.52 Wm(-1)K(-1) is attained in the 10 at.% S substituted film. Figure-of-merit ZT values of 0.15 at RT and 0.21 at 375 K are achieved. For AT of 45 K, a maximum power output of 0.32 mu W with an open-circuit voltage VOC of 12 mV is demonstrated using a TE-generator (Flex-TEG) with two thermocouples made of the prepared material. (c) 2021 Elsevier Ltd. All rights reserved.

Automated summary

This study presents a facile method to prepare a flexible thermoelectric film with enhanced performance. The film exhibits exceptional flexibility with minimal change in resistance after multiple bending cycles. By substituting a specific element, the power factor and thermal conductivity of the film are improved, resulting in higher figure-of-merit values at both room temperature and elevated temperatures. The fabricated film is demonstrated to generate power and voltage in a thermoelectric generator.