In situ photocatalytically enhanced thermogalvanic cells for electricity and hydrogen production

Yijin Wang; Youzi Zhang; Xu Xin; Jiabao Yang; Maohuai Wang; Ruiling Wang; Peng Guo; Wenjing Huang; Ana Jorge Sobrido; Bingqing Wei; Xuanhua Li

doi:10.1126/science.adg0164

In situ photocatalytically enhanced thermogalvanic cells for electricity and hydrogen production

Science. 2023 Jul 21;381(6655):291-296. doi: 10.1126/science.adg0164. Epub 2023 Jul 20.

Authors

Yijin Wang^{1

2}, Youzi Zhang^{1

2}, Xu Xin^{1

2}, Jiabao Yang^{1

2}, Maohuai Wang³, Ruiling Wang^{1

2}, Peng Guo^{1

2}, Wenjing Huang⁴, Ana Jorge Sobrido⁵, Bingqing Wei⁶, Xuanhua Li^{1

2}

Affiliations

¹ State Key Laboratory of Solidification Processing, Center for Nano Energy Materials, School of Materials Science and Engineering, Northwestern Polytechnical University, Xi'an 710072, P. R. China.
² Research and Development Institute of Northwestern Polytechnical University, Shenzhen 518057, P. R. China.
³ Department of Materials Science and Engineering, City University of Hong Kong, Hong Kong SAR, P. R. China.
⁴ School of Materials Science and Engineering, Nanyang Technological University, Singapore 639798, Singapore.
⁵ School of Engineering and Materials Science, Faculty of Science and Engineering, Queen Mary University of London, Mile End Road, London E1 4NS, UK.
⁶ Department of Mechanical Engineering, University of Delaware, Newark, DE 19716, USA.

PMID: 37471552
DOI: 10.1126/science.adg0164

Abstract

High-performance thermogalvanic cells have the potential to convert thermal energy into electricity, but their effectiveness is limited by the low concentration difference of redox ions. We report an in situ photocatalytically enhanced redox reaction that generates hydrogen and oxygen to realize a continuous concentration gradient of redox ions in thermogalvanic devices. A linear relation between thermopower and hydrogen production rate was established as an essential design principle for devices. The system exhibited a thermopower of 8.2 millivolts per kelvin and a solar-to-hydrogen efficiency of up to 0.4%. A large-area generator (112 square centimeters) consisting of 36 units yielded an open-circuit voltage of 4.4 volts and a power of 20.1 milliwatts, as well 0.5 millimoles of hydrogen and 0.2 millimoles of oxygen after 6 hours of outdoor operation.