The Application of Crystallization Kinetics in Optimizing Morphology of Active Layer in Non-Fullerene Solar Cells

Abstract

Organic photovoltaics (OPVs) have attracted widespread attention and became an important member of clean energy. Recently, their power conversion efficiency (PCE) has surpassed 19%. As is well known, the morphology of the active layer in OPVs crucially influences the PCE. In consideration of the intricate interactions between the donor molecules and acceptor molecules, the precise control of the morphology of the active layer is extremely challenging. Hence, it is urgent to develop effective methods to fabricate the hierarchical structure of the active layer. One significant driving force for the morphological evolution of the active layer is crystallization. Therefore, regulating the crystallization kinetics is an effective strategy for morphology control. In this review, we present the kinetic strategies recently developed to highlight their significance and effectiveness in morphology control. By applying these kinetic strategies, the hierarchical structure, including phase separation, domain size, crystallinity, and molecular orientation of the active layer can be optimized in different blend systems, leading to an improved PCE of OPVs. The outcomes set the stage for future advancements in device performance.