Geometrical Hierarchy-Derived Optical Asymmetry for Photovoltaic Application

In the quest for efficient and sustainable energy sources, a photovoltaic technique has emerged as a promising solution for harnessing solar energy. The primary strategy for facilitating this technique is to achieve efficient light absorption and/or manipulation of light propagation inside the media. This study presents a novel design to remarkably improve the efficiency of photovoltaic devices by incorporating the concept of optical asymmetry. The proposed structure features multidimensional and hierarchical geometry that differ hundreds of times, allowing anomalous light propagation within the media. It phenomenologically shows the notable light-trapping effect at a wide wavelength regime, thereby enhancing the overall short-circuit current by up to 46.19%. Taking a step forward, we explored the leverage of this structural design for the wavelength-converting material. Targeting the photon excitation regime of the photoactive layers, we observed a significant improvement of short-circuit current density up to 25.97% in the semi-transparent photovoltaic system at indoor light illumination. We believe this research opens up new avenues to externally optimize such photovoltaic systems, paving the way for more efficient and sustainable solar energy utilization.