Waterborne Acrylic Resin Containing Luminescent Eu3+ Pigments for Luminescent Solar Concentrators

This study reports the use of waterborne acrylic resin as a polymer matrix for thin-film luminescent solar concentrators (LSC). A water dispersable lanthanide complex based on commercially available Eu3+ chelate (Lumilux SDP Red, Lu Red) is utilized as the red-emitting pigment. The derived thin polymer films of about 100 mu m show absorptions of the organic ligand comprised between 300 and 400 nm, flanked by scattering phenomena caused by the presence of the micro-sized pigment particles, whose dispersion is not adversely affected by concentration. The film's emission displays the typical fluorescence of Eu3+ chelates around 600 nm with quantum yields between 20 and 36%. External quantum efficiencies (eta(ext)) are found to increase up to 4-4.5% with Lu Red content less than 10-15%, while dropping to about 3% at the highest content, possibly due to the adverse influence of the scattering phenomena within the waveguide. Maximum device efficiencies (eta(dev)) of 0.70% confirm the potentiality offered by the new LSC systems, thus definitely supporting the waterborne polymer matrices for the development of high-performance and water-based solar collectors.