Perovskite solar cells (PSCs) have emerged as the most promising photovoltaics because of the solution processability of the ambipolar perovskite absorber, although the adjacent transporting layers (TLs) generally bring about severe cost and processing consumptions. In this work, we propose an ultrathick solution-processed FAPbI₃ (FA: formamidinium)/MAPbI₃ (MA: methylammonium) bilayer for efficient solar cells without TLs, which only consists of two perovskites sandwiched between two electrodes. The developed room-temperature dynamic dropping technique enables fast crystallization of MAPbI₃ onto the as-fabricated FAPbI₃ without harmful redissolution and unlocks the limitation of film thickness via repeatedly dropping. By carefully controlling the thickness, buried alignment, and self-doping of two perovskites, superior semiconductor qualities and sufficient light capture of the perovskite hetero-bilayer promote the resultant TL-free PSC to a record efficiency of 16.57%. Our pioneer efforts take advantage of hetero-bilayer merits in constructing efficient all-perovskite TL-free PSCs for easily processed and cost-effective commercial requirements.

由于双极性钙钛矿吸收剂的溶液加工性，钙钛矿太阳能电池 (PSC) 已成为最有前途的光伏电池，尽管相邻的传输层 (TL) 通常会带来严重的成本和加工消耗。在这项工作中，我们提出了一种超厚溶液处理的 FAPbI ₃（FA：甲脒）/MAPbI ₃（MA：甲基铵）双层，用于没有 TL 的高效太阳能电池，它仅由夹在两个电极之间的两个钙钛矿组成。开发的室温动态滴加技术使 MAPbI 3 快速结晶到制成的_FAPbI 3_上无有害的再溶解，并通过反复滴落解锁膜厚度的限制。通过仔细控制两种钙钛矿的厚度、掩埋排列和自掺杂，钙钛矿异质双层的卓越半导体质量和足够的光捕获将所得的无 TL-free PSC 的效率提高到了 16.57% 的创纪录水平。我们的先驱工作利用异质双层的优点来构建高效的全钙钛矿无 TL PSC，以满足易于加工和具有成本效益的商业需求。