Large Voltage Generation of Flexible Thermoelectric Nanocrystal Thin Films by Finger Contact

5 years ago

Large Voltage Generation of Flexible Thermoelectric Nanocrystal Thin Films by Finger Contact

Seunggen Yang, Yoonbeom Park, Sangsig Kim, Junggwon Yun, Jinyong Choi, Kyoungah Cho

This paper demonstrates that thermal energy radiated from a human finger can be converted efficiently into electricity by a nanocrystal (NC) thin film that substantially suppresses thermal conduction, but still allows electric conduction. The converting efficiencies of the chalcogenide NC thin films with dimensions 40 µm × 20 µm × 20 nm, prepared on flexible substrates by a solution process, are maximized by adjusting the NC size. A Seebeck coefficient of S = 1829 µV K−1, and a dimensionless thermoelectric figure-of-merit, ZT = 0.68 are achieved at ambient temperature for p- and n-type NC thin films, respectively. A thermoelectric array consisting of p- and n-type NC thin films generates a voltage of 645 mV for a temperature gradient of 10 K. Furthermore, the donut-shaped pn array can generate a voltage of 170 mV from the heat supplied by an individual's finger. For solution-processable chalcogenide nanocrystal thin films, a Seebeck coefficient of 1829 µV K−1 and a dimensionless thermoelectric figure-of-merit of 0.68 are achieved at ambient temperature. The thermoelectric 20 pn pair array generates a voltage of 170 mV from the temperature difference between an individual's finger and the platform's environment.

Publisher URL: http://onlinelibrary.wiley.com/resolve/doi

DOI: 10.1002/aenm.201700972