Modulation of intramolecular charge transfer in D-A functionalized pyrrolopyrazine and their application in luminescent solar concentrators

In this study, we fabricated LSCs using pyrrolopyrazine-based organic fluorophore (PP2) with an intramolecular charge transfer (ICT) function and aggregation-induced emission. PP2 incorporates unique features, including an intramolecular charge transfer (ICT) function and aggregation-induced emission. The pyrrolopyrazine core of PP2 is decorated with an electron-rich dimethylamine group and two electron-poor cyano groups, enhancing its potential for light harvesting in LSC applications. In the polymethylmethacrylate (PMMA) matrix, PP2 showed strong absorption near ultraviolet (395 nm–406 nm), emitted green-colored visible light (474 nm–478 nm), and exhibited a photoluminescence quantum efficiency (PLQY) of 67%. The external photon efficiency (η_ext) and internal photon efficiency (η_int) of the fabricated LSC under AM 1.5G illumination (1 sun) were 3.36% and 39.1%, respectively. Subsequently, we conducted an analytical simulation to estimate the η_ext and the η_int as the dimensions of the LSC were scaled up. In addition, the photovoltaic performance measurement under 1 sun showed a power conversion efficiency (η_PCE) of 1.074% with a scattering background and 0.633% without a scattering background. Thus, this research introduces PP2 as a novel fluorophore with promising prospects for advancing the field of LSC technology.