Photonics for Photovoltaics: Advances and Opportunities

Abstract

Photovoltaic systems have reached impressive efficiencies, with records in the range of 20–30% for single-junction cells based on many different materials, yet the fundamental Shockley-Queisser efficiency limit of 34% is still out of reach. Improved photonic design can help approach the efficiency limit by eliminating losses from incomplete absorption or nonradiative recombination. This Perspective reviews nanopatterning methods and metasurfaces for increased light incoupling and light trapping in light absorbers and describes nanophotonics opportunities to reduce carrier recombination and utilize spectral conversion. Beyond the state-of-the-art single junction cells, photonic design plays a crucial role in the next generation of photovoltaics, including tandem and self-adaptive solar cells, and to extend the applicability of solar cells in many different ways. We address the exciting research opportunities and challenges in photonic design principles and fabrication that will accelerate the massive upscaling and (invisible) integration of photovoltaics into every available surface.

Towards defect-free thin films of the earth-abundant absorber zinc phosphide by nanopatterning

“…47,48 The pyramidal shape is desirable due to it aiding in trapping light within the absorber layer. [49][50][51] Fig. 1d includes typical atomic force microscopy (AFM) images that are used to determine the facet orientation as a function of time, along with transmission electron microscopy (TEM) as presented below.…”

Light trapping in thin silicon solar cells: A review on fundamentals and technologies

“…75 A recent perspective by Garnett et al showcases gratings for various PV applications. 79 A popular class of two-dimensional photonic crystals are periodic nanowire and microwire arrays. [80][81][82][83][84] As one example, Garnett and Yang reported a factor 73 of path length enhancement.…”

Soft-Microstructured Transparent Electrodes for Photonic-Enhanced Flexible Solar Cells

“…Wavelength-sized photonic structures with high refractive indexes have recently been shown to allow the highest-efficiency improvements in TFSCs by reducing reflection in a broad spectral range via geometric index matching and increasing absorption in TFSCs via light scattering and coupling to waveguided modes confined in the periodic cells' structure [10,[18][19][20][21].…”