Synergistic engineering of the Stokes shift for highly efficient and stable quasi-2D perovskite luminescent solar concentrators

Abstract

Luminescent solar concentrators (LSCs) have the advantages of translucency, color tunability, wide incident light angles, and high weak light sensitivity, so they are attractive for practical applications. Reducing the reabsorption loss and increasing the photoluminescence quantum yield (PLQY) are effective strategies to improve the efficiency of LSCs. However, materials possessing small reabsorption and high PLQY simultaneously are rare. In this work, we demonstrate a strategy to overcome the reabsorption obstacle by the Stokes shift synergistic engineering of active materials. For the first time, we designed and synthesized three new quasi-2D perovskite/PVDF composite films by a room temperature solution processing method. The composite films are able to combine energy-funneling and a positive transient Stark shift to achieve a high PLQY and large Stokes shift. The composite films exhibit high water stability and improved ultraviolet (UV) stability. The large area LSC device with a size of 10 × 10 cm² exhibits a remarkable external optical efficiency (η_ext) of up to 4.9%, which is the highest value reported among organic–inorganic hybrid perovskite LSCs. This work demonstrates that the Stokes shift synergistic engineering of quasi-2D perovskite/PVDF composites is an ideal strategy for constructing efficient and stable LSC devices.