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

It has been a challenge to obtain high electrical conductivity in inorganic printed thermoelectric (TE) films due to their high interfacial resistance. In this work, we report a facile synthesis process of Cu-Se-based printable ink for screen printing. A highly conducting TE beta-Cu2-delta Se phase forms in the screen-printed Cu-Se-based film through <= 10 ms sintering using photonic-curing technology, minimizing the interfacial resistance. This enables overcoming the major challenges associated with printed thermoelectrics: (a) to obtain the desired phase, (b) to attain high electrical conductivity, and (c) to obtain flexibility. Furthermore, the photonic-curing process reduces the synthesis time of the TE beta-Cu2-delta Se film from several days to a few milliseconds. The sintered film exhibits a remarkably high electrical conductivity of similar to 3710 S cm(-1) with a TE power factor of similar to 100 mu W m(-1) K-2. The fast processing and high conductivity of the film could also be potentially useful for different printed electronics applications.

Automated summary

By studying the synthesis of copper-selenium-based printable ink and photonic-curing technology, high electrical conductivity in printed thermoelectric films was achieved while minimizing interfacial resistance. The fast processing and high conductivity of the film also show potential for various printed electronics applications.