The Synergistic Effect of Pemirolast Potassium on Carrier Management and Strain Release for High‐Performance Inverted Perovskite Solar Cells

Abstract

The quality of the perovskite absorption layer is critical for the high efficiency and long‐term stability of perovskite solar cells (PSCs). The inhomogeneity due to local lattice mismatch causes severe residual strain in low‐quality perovskite films, which greatly limits the availability of high‐performance PSCs. In this study, a multi‐active‐site potassium salt, pemirolast potassium (PP), is added to perovskite films to improve carrier dynamics and release residual stress. X‐ray photoelectron spectroscopy (XPS) and Fourier‐transform infrared spectroscopy (FTIR) measurements suggest that the proposed multifunctional additive bonds with uncoordinated Pb2+ through the carbonyl group/tetrazole N and passivated I atom defects. Moreover, the residual stress release is effective from the surface to the entire perovskite layer, and carrier extraction/transport is promoted in PP‐modified perovskite films. As a result, a champion power conversion efficiency (PCE) of 23.06% with an ultra‐high fill factor (FF) of 84.36% is achieved in the PP‐modified device, which ranks among the best in formamidinium‐cesium (FACs) PSCs. In addition, the PP‐modified device exhibits excellent thermal stability due to the inhibited phase separation. This work provides a reliable way to improve the efficiency and stability of PSCs by releasing residual stress in perovskite films through additive engineering.

Multifunctional dual-interface layer enables efficient and stable inverted perovskite solar cells

“…14,23 From the FTIR results shown in Fig. 2e, it is worth noting that the original CN vibrational mode appearing at 1600 cm −1 shifted to 1610 cm −1 , 30,31 which confirms the strong interaction between 3-PyAI and the perovskite film. Furthermore, the NH 3+ ions primarily passivate charged defects on the perovskite surface through electrostatic interactions such as ionic and hydrogen bonding.…”

Machine learning-assisted screening of effective passivation materials for P–I–N type perovskite solar cells

“…48 This reveals that the CO groups and N atoms in ITIC interact with the uncoordinated Pb 2+ ions in the perovskite film, leading to the effective suppression of defects on the surface of the perovskite film. 49,50 Moreover, it is found that a new peak appeared in the ITIC-treated perovskite film, which comes from the S atoms in ITIC, indicating that ITIC is present on the surface of the perovskite film. This finding is consistent with the results of the AFM study on the surface of the ITIC-treated perovskite film.…”

Simultaneous realization of bulk and interface regulation based on 2,4-diamino-6,7-diisopropylpteridine phosphate for efficient and stable inverted perovskite solar cells

“…The positive slopes for both kinds of films show the perovskite films subject to the compressive stress, which is similar to the result of the previous work reported by J. Li. 68 The smaller slope corresponds to the smaller residual stress in the film. Thus, the residual stress of the perovskite film also can be reduced by the DPP modification, and the perovskite film with DPP bears a slighter compressive strain.…”