Recently, perovskite solar cells (PSCs) basing on quasi-two-dimensional (quasi-2D) perovskites with hydrophobic bulky organic cations have received a lot of interests owing to their superior moisture stability. While quasi-2D perovskites have achieved great success in planar p-i-n PSCs, their application in planar n-i-p devices and the corresponding efficiencies lag far behind. In our work, (FPEA)₂(MA)₄Pb₅I₁₆ perovskite films with high crystallinity, compact and smooth surface were deposited on electron transport layer with NH₄SCN as an additive. Formamidinium (FA⁺) were then incorporated into the FPEA based perovskite films to partially replace methylammonium (MA⁺), and effects of FA⁺ on the film's vertical orientation, light absorption capacity, carrier lifetime, defect density and electron mobility were studied. It was found that when molar ratio of FA/MA = 0.5/9.5, the film had the highest vertical orientation, enhanced light absorption, less carrier recombination loss. The obtained (FPEA)₂(FA_0.05MA_0.95)₄Pb₅I₁₆ based n-i-p PSCs gave a maximum efficiency of 12.17% under standard illumination, retaining 83% of the initial efficiency after stored in air environment (25–30 °C) with 40 ± 5% RH for 1080 h. The results demonstrate an efficient approach to prepare high-quality quasi-2D perovskite films in a n-i-p structure as well as improved device efficiency and stability.

最近，基于具有疏水大体积有机阳离子的准二维（quasi-2D）钙钛矿的钙钛矿太阳能电池（PSC）由于其优异的水分稳定性而受到广泛关注。虽然准二维钙钛矿在平面 pin PSC 中取得了巨大成功，但它们在平面 nip 器件中的应用和相应的效率远远落后。在我们的工作中，(FPEA) ₂ (MA) ₄ Pb ₅ I _{16钙钛矿薄膜具有高结晶度、致密和光滑的表面，以NH 4} SCN作为添加剂沉积在电子传输层上。然后将甲脒 (FA ⁺ ) 掺入基于 FPEA 的钙钛矿薄膜中，以部分取代甲基铵 (MA ⁺), 并研究了 FA ⁺对薄膜垂直取向、光吸收能力、载流子寿命、缺陷密度和电子迁移率的影响。发现当FA/MA摩尔比=0.5/9.5时，薄膜的垂直取向最高，光吸收增强，载流子复合损失较少。得到的 (FPEA) ₂ (FA _0.05 MA _0.95 ) ₄ Pb ₅ I ₁₆基于 nip 的 PSC 在标准照明下的最大效率为 12.17%，在 40 ± 5% RH 的空气环境 (25–30 °C) 中储存 1080 小时后，保留了初始效率的 83%。结果证明了一种在 nip 结构中制备高质量准二维钙钛矿薄膜的有效方法，并提高了器件效率和稳定性。