Efficiencies of perovskite solar cells (PSCs) have risen unprecedentedly from 3.8% to 25.2% in just over a decade as the light absorber material has evolved from the original methylammonium (MA)- to formamidinium (FA)-dominated perovskite. While FA lead iodide (FAPbI₃) has a lower bandgap and, therefore, a higher theoretical efficiency limit, it is less phase stable, although this can overcome by incorporating cesium (Cs), MA, bromide (Br), or a combination of these. Cs being a nonvolatile component remains in the perovskite film and therefore it is important to understand the effect of the amount of Cs on film properties and associated PSC performance and stability. Future research opportunities for Cs-containing PSCs including large-area demonstrations are also discussed in this review.

钙钛矿太阳能电池（PSC）的效率在短短十年内就从3.8％前所未有地提高到25.2％，这是因为光吸收材料已经从最初的甲基铵（MA）变为以甲form（FA）为主的钙钛矿。尽管FA碘化铅（FAPbI ₃）具有较低的带隙，因此具有较高的理论效率极限，但其相稳定性较差，尽管可以通过掺入铯（Cs），MA，溴化物（Br）或以下物质的组合来克服这些。作为非挥发性组分的Cs残留在钙钛矿膜中，因此重要的是要了解Cs的量对膜性能以及相关的PSC性能和稳定性的影响。本文还讨论了含Cs的PSC的未来研究机会，包括大面积的示范。