Efficient Rigid and Flexible Perovskite Solar Cells with Uniform Crystallization and Weak Lattice Vibration via Interface Defect Passivation

Interface molecules with strong adsorption energies on (100) facets coordinate with lead and iodine ions and reduce the ion defects, leading to uniform and crystalline perovskite and efficient perovskite solar cells (PVSCs). Herein, we demonstrate efficient and stable rigid and flexible PVSCs via defect passivation using 1,3-dibromo-1,3,5-triazine-2,4,6-trione hydrochloride. The molecular passivation enabled a crystalline and uniform perovskite with weak lattice shrinkage. The rigid and flexible PVSCs yield high power conversion efficiencies of 25.50% and 24.56%, respectively. Furthermore, both PVSCs exhibit substantial enhancement in operational stability. Under the maximum power point tracking measurement, the T₉₀ lifetime (time for the device's efficiency to decrease to 90% of its initial efficiency) of the flexible PVSCs is 1100 h, which is the best result among these flexible inverted PVSCs reported so far. The work provides a multifunctional passivation strategy and valuable insights into making high-performance PVSCs.