Energy harvesting textiles: using wearable luminescent solar concentrators to improve the efficiency of fiber solar cells

Abstract

Fiber solar cells have attracted considerable interest in recent years for their agile integration with wearable electronics. They have the unique advantage of collecting light from all directions. However, in daily use, the incoming sunlight only covers the face-up surface area and a large portion of it is lost between fiber gaps, leading to an unexploited device efficiency. In this work, wearable luminescent solar concentrators (LSCs) are integrated with fiber solar cells to harvest additional photons and fully utilize the advantage of harvesting light from all directions. Wearable LSCs made from an amphiphilic polymer conetwork matrix and coumarin 6 luminescent dyes are applied to fiber dye-sensitized solar cells (FDSSCs). The results show a remarkable FDSSC power conversion efficiency enhancement of 84%, LSC concentration factor of 1.57, and device optical efficiency of 7.85%, attributed to LSC-assisted enlargement of the photon harvesting area, recycling of lost photons, and utilization of the complete surface of FDSSCs. Using a Monte Carlo ray-tracing simulation for optimizing the fibers' arrangement, a textile with multiple FDSSCs integrated with 3 cm² LSCs exhibits a high-power output of 0.89 mW. The device shows a sustainable power conversion efficiency even after 1000 bending cycles, which demonstrates its wearability. This is the first experimental and computational demonstration of the integration of FDSSCs and wearable LSCs as energy harvesting textiles, showcasing their potential as future wearable electronic systems.