Highly Efficient Luminescent Solar Concentrators Based on BODIPY Derivatives

Abstract

Three new chromophores based on difluoroborondipyrromethene dyes (Bodipy-1, Bodipy-2, and Bodipy-3) are used as precursors to prepare luminescent solar concentrators (LSC) based on poly-acrylate, following a thermally activated polymerization involving lauryl methacrylate as monomer, ethyl glycol dimethacrylate as cross-linking agent, and lauroyl peroxide as initiator. The new dyes exhibit typical BODIPY absorption and emission properties in dichloromethane fluid solution, assigned to the lower-lying singlet π–π∗ level, which in the case of Bodipy-2 and Bodipy-3, both containing diamino-substituted styryl subunits in their structure, has a strong charge transfer contribution. The LSCs obtained starting from each of the three Bodipys are interfaced to silicon photovoltaic (PV) cells, and the PV light-to-energy conversion efficiencies ηopt for the three systems are calculated. The results yield ηopt of 4.53% for LSC-Bodipy-1, 5.26% for LSC-Bodipy-2, and 8.23% for LSC-Bodipy-3. The optical efficiency for LSC-Bodipy-3 is a remarkable value among the LSC based on organic dyes.