Semi-Transparent Solar Cell enabled by Frequency Selective Light Trapping

TL;DR

This paper introduces a frequency selective light trapping method for semitransparent solar cells, significantly improving transparency while maintaining high efficiency through nanoparticle scattering and photonic stacking.

Contribution

It presents a novel frequency selective scattering layer using TiO2 nanoparticles and a photonic stack, enhancing transparency and efficiency in silicon solar cells.

Findings

Achieved 12.0% efficiency with 60.2% visible transparency.

Enhanced transparency by 13.3% compared to bare silicon cells.

Demonstrated the effectiveness of frequency selective light trapping through numerical simulations.

Abstract

We propose a frequency selective light trapping scheme that enables the creation of more visually-transparent and yet simultaneously more efficient semitransparent solar cells. A nanoparticle scattering layer and photonic stack back reflector create a selective trapping effect by total internal reflection within a medium, increasing absorption of IR light. We propose a strong frequency selective scattering layer using spherical TiO2 nanoparticles with radius of 255 nm and area density of 1.1% in a medium with index of refraction of 1.5. Using detailed numerical simulations for this configuration, we find that it is possible to create a semitransparent silicon solar cell that has a Shockley Queisser efficiency of 12.0%\pm0.4% with a visible transparency of 60.2%\pm1.3%, 13.3%\pm1.3 more visibly-transparent than a bare silicon cell at the same efficiency.