The energy landscape of reduced-dimensional perovskites (RDPs) can be tailored by adjusting their layer width (n). Recently, two/three-dimensional (2D/3D) heterostructures containing n = 1 and 2 RDPs have produced perovskite solar cells (PSCs) with >25% power conversion efficiency (PCE). Unfortunately, this method does not translate to inverted PSCs due to electron blocking at the 2D/3D interface. Here we report a method to increase the layer width of RDPs in 2D/3D heterostructures to address this problem. We discover that bulkier organics form 2D heterostructures more slowly, resulting in wider RDPs; and that small modifications to ligand design induce preferential growth of n ≥ 3 RDPs. Leveraging these insights, we developed efficient inverted PSCs (with a certified quasi-steady-state PCE of 23.91%). Unencapsulated devices operate at room temperature and around 50% relative humidity for over 1,000 h without loss of PCE; and, when subjected to ISOS-L3 accelerated ageing, encapsulated devices retain 92% of initial PCE after 500 h.

可以通过调整其层宽 ( n )来定制降维钙钛矿 (RDP) 的能量景观。最近，包含n = 1 和 2 个 RDP的二维/三维（2D/3D）异质结构 已经生产出功率转换效率（PCE）>25% 的钙钛矿太阳能电池（PSC）。不幸的是，由于 2D/3D 界面处的电子阻挡，这种方法不能转化为倒置 PSC。在这里，我们报告了一种增加 2D/3D 异质结构中 RDP 层宽度的方法，以解决这个问题。我们发现体积更大的有机物形成二维异质结构的速度更慢，导致 RDP 更宽；并且对配体设计的小修改会导致n的优先增长 ≥ 3 个 RDP。利用这些见解，我们开发了高效的倒置 PSC（经认证的准稳态 PCE 为 23.91%）。未封装的器件在室温和 50% 左右的相对湿度下运行超过 1,000 小时而不会损失 PCE；并且，当经受 ISOS-L3 加速老化时，封装器件在 500 小时后保留 92% 的初始 PCE。