Envisioning the future: optically transparent metasurface-based solar thermophotovoltaic with high conversion efficiency

Transparent solar thermo-photovoltaic (TPV) technology combines visible transparency and solar energy conversion. They are developed for their potential applications in buildings and vehicles windows, where conventional opaque solar cells may not be feasible. TPV's offer a promising solution to harness solar energy without compromising aesthetics or functionality of transparent surfaces. Broadband absorption at UV and IR frequencies and simultaneous transmission at visible frequencies can be achieved by fabricating metamaterials that employ semi-conducting oxides. In this study, an optically transparent metasurface (OTM) based STPV composed of indium tin oxide (ITO) is introduced as the transparent metal and ZnS as a substrate layer. Our design offers a cost-effective and scalable solution for large-scale fabrication. The designed OTM structure exhibits exceptional absorption capabilities, achieving an absorption rate of up to 99% in the UV region. Additionally, it achieves over 90% absorptivity in the far infrared range and maintains a high average transmittance at visible frequencies. Furthermore, the absorption remains consistently high, exceeding 90%, even when the incident angle is less than 70 degrees for both TE and TM polarization waves. This innovative design holds promise for various applications requiring high-performance transparent metasurface absorbers/emitters. The proposed transparent metasurface based STPV holds great potential for efficient utilization in combined solar/thermal conversion systems.