Multifunctional 1-naphthoic acid additive enhancing ultraviolet stability of perovskite solar cells

Abstract

Perovskite solar cells (PSCs) have achieved remarkable power conversion efficiency (PCE), but their instability under ultraviolet (UV) illumination remains a critical barrier to commercialization. Here, we introduce 1-naphthoic acid (1-NA) as a small and multifunctional additive to mitigate UV-induced degradation in PSCs. The 1-NA molecule stabilizes the perovskite lattice, suppresses ion migration, enhances structural integrity, and reduces UV photodegradation through passivation and high-energy photon conversion via energy relaxation processes. The champion device incorporating 1-NA achieved a PCE of 25.36%. Crucially, the 1-NA engineered device exhibits an exceptional optimization effect on operational stability. It retains 84% of its initial PCE after 240 hours under intense UV light (50 mW cm⁻²), compared to only 37% for the control, and maintains 83% after 1000 hours of continuous AM1.5G illumination. This work provides a robust strategy for developing high-efficiency perovskite optoelectronic devices with good stability through rational molecular engineering.