Solar harvesting based on perfect absorbing all-dielectric nanoresonators on a mirror

Abstract

The high-index all-dielectric nanoantenna system is a platform recently used for multiple applications, from metalenses to light management. These systems usually exhibit low absorption/scattering ratios and are not efficient photon harvesters. Nevertheless, by exploiting far-field interference, all-dielectric nanostructures can be engineered to achieve near-perfect absorption in specific wavelength ranges. Here, we propose-based on electrodynamics simulations-that a metasurface composed of an array of hydrogenated amorphous silicon nanoparticles on a mirror can achieve nearly complete light absorption close to the bandgap. We apply this concept to a realistic device, predicting a boost of optical performance of thin-film solar cells made of such nanostructures. In the proposed device, high-index dielectric nanoparticles act not only as nanoatennas able to concentrate light but also as the solar cell active medium, contacted at its top and bottom by transparent electrodes. By optimization of the exact geometrical parameters, we predict a system that could achieve initial conversion efficiency values well beyond 9%-using only the equivalent of a 75-nm thick active material. The device absorption enhancement is 50% compared to an unstructured device in the 400 nm − 550 nm range and more than 300% in the 650 nm − 700 nm spectral region. We demonstrate that such large values are related to the metasurface properties and to the perfect absorption mechanism.

Ultrathin Film Amorphous Silicon Solar Cell Performance using Rigorous Coupled Wave Analysis Method

“…The plasmonic nanostructures can support the localized surface plasmon resonances which are the collective oscillation of the conducting electrons. Furthermore, the physics of the highest absorption peaks of ultrathin amorphous silicon solar cells are explored by electromagnetic theory (Maxwell's equations) (Isabella et al, 2018;Vismara et al, 2019). The spectral peaks are corresponding to the surface, guided modes, Fabry-Perot resonance, Floquet mode, surface plasmon resonance, constructively interfere between the metallic and semiconductors.…”

Optical nanoresonators

“…3) An important area of application of optical nanocavities is to increase the efficiency of solar cells, and for this purpose, not only plasmonic, but also dielectric nanoresonators are used [173][174][175][176][177].…”

Helical SiNW design with a dual-peak response for broadband scattering in translucent solar cells

“…Nanowires have excellent optical and electrical properties to be widely used in photovoltaics, photoelectric, sensors, biology, and other fields. [1][2][3][4][5][6][7] Silicon nanowire (SiNW) is a typical semiconductor nanowire, which combines the semiconductor properties of Si materials and nano-scale optical effects. [8][9][10] It is applied in photoelectric conversion and energy storage devices.…”