Broadband perfect absorbers in the visible region have attracted considerable attention in many fields, especially in solar thermophotovoltaic and energy harvesting systems. However, developing light absorbers with high absorptivity, thermal stability, and a broad bandwidth remains a great challenge. Here, we theoretically and experimentally demonstrate that a titanium nitride metasurface absorber exhibits broadband absorption with an average absorption of more than 92% over a wavelength range of 400 to 750 nm. The increase in absorption is attributed to the localized surface plasmon resonance (LSPR). We demonstrate the plasmon-enhanced visible-light-driven hydrogen production from water using a polymer photocatalyst integrated with a TiN metasurface absorber. A 300% increase in the hydrogen evolution rate was observed due to the LSPR that enhances the rates of light absorption, carrier separation, and hot-carrier transfer in polymer photocatalyst. These results enable a new approach to prepare high-efficiency solar energy harvesting systems.
Bibliographical noteKAUST Repository Item: Exported on 2021-10-19
Acknowledged KAUST grant number(s): Award No. OSR-2018-CARF/CCF-3079.
Acknowledgements: The authors would like to thank Jia-Wern Chen, Dr. Cheng-Hung Chu, Tomoki Watanabe, and Prof. Masanobu Haraguchi for useful discussions. We also acknowledge use of an optical measurement setup supported by Prof. Min-Hsiung Shih. We acknowledge financial support from the Ministry of Science and Technology, Taiwan (Grant No. MOST-109-2112-M-001-043-MY3 (Y.J.L.); MOST-110-2124-M-001-008-MY3 (Y.J.L.); MOST-110-2636-E-007-020 (H.H.C.); MOST-110-2622-8-007-015 (H.H.C.)) and Academia Sinica (Grant No. AS-CDA-108-M08 (Y.J.L.)). H.W.L. acknowledges the financial support from the AFOSR-AOARD (Award Number: FA2386-18-1-4099). V.T. is indebted to the support from the King Abdullah University of Science and Technology (KAUST) Office of Sponsored Research (OSR) under Award No. OSR-2018-CARF/CCF-3079.
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Atomic and Molecular Physics, and Optics
- Electrical and Electronic Engineering