Giant thermopower of ionic gelatin near room temperature

Cheng-Gong Han; Xin Qian; Qikai Li; Biao Deng; Yongbin Zhu; Zhijia Han; Wenqing Zhang; Weichao Wang; Shien-Ping Feng; Gang Chen; Weishu Liu

doi:10.1126/science.aaz5045

Giant thermopower of ionic gelatin near room temperature

Science. 2020 Jun 5;368(6495):1091-1098. doi: 10.1126/science.aaz5045. Epub 2020 Apr 30.

Authors

Cheng-Gong Han^{1

2}, Xin Qian³, Qikai Li^{1

4}, Biao Deng¹, Yongbin Zhu¹, Zhijia Han¹, Wenqing Zhang⁵, Weichao Wang⁶, Shien-Ping Feng⁴, Gang Chen⁷, Weishu Liu^{8

2}

Affiliations

¹ Department of Materials Science and Engineering, Southern University of Science and Technology, Shenzhen, Guangdong 518055, China.
² Shenzhen Engineering Research Center for Novel Electronic Information Materials and Devices, Southern University of Science and Technology, Shenzhen, Guangdong 518055, China.
³ Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
⁴ Department of Mechanical Engineering, The University of Hong Kong, Pokfulam, Hong Kong 999077, China.
⁵ Department of Physics and Shenzhen Institute for Quantum Science and Technology, Southern University of Science and Technology, Shenzhen, Guangdong 518055, China.
⁶ Department of Electronics and Tianjin Key Laboratory of Photo-Electronic Thin Film Device and Technology, Nankai University, Tianjin 300071, China.
⁷ Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA. liuws@sustech.edu.cn gchen2@mit.edu.
⁸ Department of Materials Science and Engineering, Southern University of Science and Technology, Shenzhen, Guangdong 518055, China. liuws@sustech.edu.cn gchen2@mit.edu.

PMID: 32354840
DOI: 10.1126/science.aaz5045

Abstract

Harvesting heat from the environment into electricity has the potential to power Internet-of-things (IoT) sensors, freeing them from cables or batteries and thus making them especially useful for wearable devices. We demonstrate a giant positive thermopower of 17.0 millivolts per degree Kelvin in a flexible, quasi-solid-state, ionic thermoelectric material using synergistic thermodiffusion and thermogalvanic effects. The ionic thermoelectric material is a gelatin matrix modulated with ion providers (KCl, NaCl, and KNO₃) for thermodiffusion effect and a redox couple [Fe(CN)₆ ^4-/Fe(CN)₆ ^3-] for thermogalvanic effect. A proof-of-concept wearable device consisting of 25 unipolar elements generated more than 2 volts and a peak power of 5 microwatts using body heat. This ionic gelatin shows promise for environmental heat-to-electric energy conversion using ions as energy carriers.

Publication types

Research Support, Non-U.S. Gov't