Impact of Functional Fluorinated Porphyrins on the Efficiency and Stability of Perovskite Solar Cells.

Additives play a pivotal role in enhancing the efficiency of perovskite solar cells (PSCs), and carefully designed additives contribute to major breakthroughs in device performance. In this study, a series of novel A-π-A-type porphyrin derivatives-PPH-1, PPH-2, and PPF-1-are synthesized, each incorporating pyridyl groups, specifically engineered to function as passivation agents for PSCs. The electron-withdrawing properties of fluorine in PPF-1 increase the molecular polarity, thereby strengthening its interaction with the perovskite and enhancing the passivation efficacy. Compared to PPH-1 and PPH-2, PPF-1 not only improves crystallinity but also provides more efficient defect passivation at grain boundaries and interfaces. As a result, PSCs incorporating PPF-1 achieve a remarkable power conversion efficiency (PCE) of 24.96%, along with an open-circuit voltage (V) of 1.178 V, a short-circuit current density (J) of 24.65 mA cm, and a fill factor (FF) of 85.96%, surpassing the PCEs of 23.36%, 24.11%, and 23.93% for pristine, PPH-1-, and PPH-2-modified PSCs, respectively. In addition, the incorporation of fluorinated porphyrin in PPF-1 significantly improves the moisture resistance and thermal stability, while the device maintains high solar efficiency, opening up new alternative ways to promote solar cell innovation.