Design and Response of High-Efficiency, Planar, Doped Luminescent Solar Concentrators Using Organic-Inorganic Di-Ureasil Waveguides

Luminescent solar concentrators (LSCs) offer significant potential for solar energy capture in the urban environment. Here, the first example of a planar, doped LSC using Lumogen Red (LR305) as the luminophore and a di-ureasil organic-inorganic hybrid as the waveguide is reported. The di-ureasil waveguide offers several advantages over organic polymer waveguides including facile solution-processing from benign solvents and extension of the absorption window through energy transfer. Spectral evaluation using absorption and photoluminescence spectroscopies is used to optimize the LSC composition, yielding optical efficiencies as high as 14.5% (300-800 nm). A power conversion efficiency (PCE) of 0.54% is obtained for the champion LSC coupled to a c-Si PV cell using the di-ureasil precursor as an optical glue to minimize interfacial losses. Finally, a simple figure of merit to evaluate the performance of LSC-solar cell composite systems is proposed that enables comparison of the actual improvement in the efficiency of solar cells due to the attachment of the LSC, irrespective of the LSC design, architecture or materials. A PCE of 17.4% for the solar cell in the emission region of the LSC is obtained, which is a remarkable improvement of approximate to 40% over its AM 1.5G value.