Printed thermoelectric materials and devices: Fabrication techniques, advantages, and challenges

Thermoelectric (TE) devices enable increased efficiency and performance by converting waste heat to usable electricity or providing solid-state, localized cooling. Large-scale implementation of the technology is hindered by power conversion efficiency, manufacturing challenges, and material and system costs. Traditionally, inorganic compounds like bismuth telluride and lead telluride are used for their high performance, but they are brittle, scarce, and toxic. Organic compounds have lower power conversion efficiencies, but they are flexible, abundant, low-cost, environmentally benign, and solution-processable, making them suitable for large-scale, high-throughput manufacturing techniques such as roll-to-roll printing. Inorganic-organic hybrid composite materials can boost power conversions efficiencies while maintaining ease of processing. This review summarizes and compares four manufacturing techniques-inkjet, screen, and dispenser printing, and stereolithography-used to fabricate TE devices. Common challenges relevant to printed TE materials and devices are described, and recent research results using these techniques are also reviewed. (C) 2016 Wiley Periodicals, Inc.