Halogenated and Dopant-free Hole Transport Materials for n-i-p Perovskite Solar Cells

environment, devices based on fluorine-substituted groups maintained 85% of their initial efficiency, while devices based on chlorine-substituted groups showed a decrease to approximately 30% of their initial efficiency after only 700 h. The findings suggest that fluorine-substituted organic HTLs have a significant effect on the photovoltaic performance of PSCs, highlighting their potential in developing high-performance organic HTMs for future applications.