Fabricating a scattering–fluorescent luminescent solar concentrator synchronously to achieve broad-spectrum solar energy utilization and light pollution inhibition

Abstract

Light pollution caused by the reflected light of buildings poses a growing threat to the global environment and human health. Currently, the common luminescent solar concentrator (LSC), as an important transparent photovoltaic component for building-integrated photovoltaics (BIPV), is unable to reduce light pollution due to the limited utilization of solar energy only in the ultraviolet range. In this study, a scattering–fluorescent LSC (S–F LSC) is fabricated using a particular two-step strategy with an electrostatic assembly of a microfibrillated cellulose (MFC)/carbon quantum dot (CQD) composite and its embedment into PMMA through in situ radical bulk polymerization. S–F LSC exhibits the dual characteristics of visible light scattering and fluorescent luminescence while maintaining 77.87% transmittance. After its combination with a silicon solar cell, the formed PV-LSC device shows the capability to utilize natural light in both visible and UV spectral bands. With 1.6 wt% MFC/CQDs composites in S–F LSC, the external optical efficiency and power conversion efficiency are up to 18.07% and 8.61%, respectively, under a standard sunlight condition (100 mW cm⁻²). Only 9.99% reflection of visible light of S–F LSC is produced. The synergistic function of the broad-spectrum solar energy utilization and light pollution inhibition provides S–F LSC with the potential to become key transparent energy-saving components in BIPV for livable outdoor and indoor lifestyles.