Recently, the two-dimensional (2D) ruddlesden-popper (RPP) perovskite has been successfully attracting great attention owing to their excellent electronic property and superior ambient stability. But 2D perovskite solar cells (PVSCs) with insulating large cations show a worse performance than three-dimensional (3D) PVSCs in general because of the worse charge transportation. In this work, dimethyl sulfoxide (DMSO) and KI were incorporated simultaneously to produce a synergistic effect on both film quality and orientation of 2D perovskite. With this strategy, a cavity-free 2D perovskite film was formed with vertically oriented crystal, and high quality film was obtained with decreased defects and increased crystallinity. Besides, profitable multiple phases were obtained for better spontaneous carrier separation and transportation. The 2D PVSCs based on (PEA)₂(MA)_n−1PbnI_3n+1 (n=5) delivered a higher power conversion efficiency (PCE) of 13.4%. In addition, the perovskite with KI and DMSO contained more stable low-dimension phase at the bottom of perovskite film, which could act as a barrier to prevent moisture from further eroding internal perovskites. The optimized 2D PVSCs remained 90% of the PCE after being exposed in air (50%–60% humidity, room temperature) with a continuous illumination for 300 h.

近年来，二维（2D）ruddlesden-popper（RPP）钙钛矿因其出色的电子性能和出色的环境稳定性而受到了广泛的关注。但是，由于电荷传输较差，具有绝缘大阳离子的2D钙钛矿太阳能电池（PVSC）显示的性能通常比3维（3D）PVSC差。在这项工作中，同时加入了二甲基亚砜（DMSO）和KI，以对薄膜质量和2D钙钛矿的取向产生协同作用。通过这种策略，可以形成具有垂直取向晶体的无腔二维钙钛矿薄膜，并获得具有减少的缺陷和增加的结晶度的高质量薄膜。另外，获得了有利的多相，以更好地自发分离和运输载体。₂（MA）_{n -1} PbnI _{3 n +1}（n = 5）提供了13.4％的更高功率转换效率（PCE）。另外，含有KI和DMSO的钙钛矿在钙钛矿膜的底部含有更稳定的低维相，这可以作为阻挡层，防止水分进一步侵蚀内部钙钛矿。经过优化的2D PVSC在空气中（持续50％–60％的湿度，室温）暴露300 h后仍保持PCE的90％。