Enhancing solar-thermal energy conversion with silicon-cored tungsten nanowire selective metamaterial absorbers

Jui-Yung Chang; Sydney Taylor; Ryan McBurney; Xiaoyan Ying; Ganesh Allu; Yu-Bin Chen; Liping Wang

doi:10.1016/j.isci.2020.101899

Enhancing solar-thermal energy conversion with silicon-cored tungsten nanowire selective metamaterial absorbers

iScience. 2020 Dec 7;24(1):101899. doi: 10.1016/j.isci.2020.101899. eCollection 2021 Jan 22.

Authors

Jui-Yung Chang^{1

2

3}, Sydney Taylor¹, Ryan McBurney¹, Xiaoyan Ying¹, Ganesh Allu², Yu-Bin Chen^{3

4}, Liping Wang¹

Affiliations

¹ School for Engineering of Matter, Transport & Energy, Arizona State University, Tempe, AZ 85287, USA.
² Department of Mechanical Engineering, National Chiao Tung University, Hsinchu 300, Taiwan.
³ Department of Power Mechanical Engineering, National Tsing Hua University, Hsinchu 300, Taiwan.
⁴ Department of Mechanical Engineering, National Cheng Kung University, Tainan 70101, Taiwan.

Abstract

This work experimentally studies a silicon-cored tungsten nanowire selective metamaterial absorber to enhance solar-thermal energy harvesting. After conformally coating a thin tungsten layer about 40 nm thick, the metamaterial absorber exhibits almost the same total solar absorptance of 0.85 as the bare silicon nanowire stamp but with greatly reduced total emittance down to 0.18 for suppressing the infrared emission heat loss. The silicon-cored tungsten nanowire absorber achieves an experimental solar-thermal efficiency of 41% at 203°C during the laboratory-scale test with a stagnation temperature of 273°C under 6.3 suns. Without parasitic radiative losses from side and bottom surfaces, it is projected to reach 74% efficiency at the same temperature of 203°C with a stagnation temperature of 430°C for practical application, greatly outperforming the silicon nanowire and black absorbers. The results would facilitate the development of metamaterial selective absorbers at low cost for highly efficient solar-thermal energy systems.

Keywords: Energy Materials; Nanomaterials; Thermal Engineering; Thermal Property.