Regulating buried interface properties and alleviating micro-strain of crystals for efficient perovskite solar cells

Abstract

Surface properties of SnO₂ and their effects on the growth of perovskite films play a crucial role for perovskite solar cells (PSCs). Herein, a facile strategy to synchronously regulate the buried interface defects and energy level arrangement, as well as improve the crystallinity of perovskite films with alleviated micro-strain by pre-modifying the SnO₂ surface with ammonium hexafluorophosphate (NH₄PF₆) is proposed. The device achieved the promising PCE of 22.50% and improved stability.