Organic π-type thermoelectric module supported by photolithographic mold: a working hypothesis of sticky thermoelectric materials

ABSTRACT

To examine the potential of organic thermoelectrics (TEs) for energy harvesting, we fabricated an organic TE module to achieve 250 mV in the open-circuit voltage which is sufficient to drive a commercially available booster circuit designed for energy harvesting usage. We chose the π-type module structure to maintain the temperature differences in organic TE legs, and then optimized the p- and n-type TE materials’ properties. After injecting the p- and n-type TE materials into photolithographic mold, we eventually achieved 250 mV in the open-circuit voltage by a method to form the upper electrodes. However, we faced a difficulty to reduce the contact resistance in this material system. We conclude that TE materials must be inversely designed from the viewpoints of the expected module structures and mass-production processes, especially for the purpose of energy harvesting.

GRAPHICAL ABSTRACT

KEYWORDS:

• Contact resistance
• flexible thermoelectric sheet
• mass-production
• inverse materials design

CLASSIFICATION:

• 50 Energy Materials; 210 Thermoelectronics / Thermal transport / insulators

Acknowledgments

The study was financially supported by NIMS and Denka. Kyowa Chemical Industry Co., Ltd. provided KW-1000S. We thank K. Ogata for his technical assistance on the ZEM-3 measurement.

Disclosure statement

No potential conflict of interest was reported by the authors.

Supplementary material

Supplemental data for this article can be accessed here.

Additional information

Funding

This work was supported by the National Institute for Materials Science [PE416]; Denka Company Limited [NA002].