Whereas lead halide perovskite-based colloidal quantum dots (PQDs) have emerged as a promising photoactive material for solar cells, the research to this point has predominantly focused on inorganic cation PQDs despite the fact that organic cation PQDs have more favourable bandgaps. In this work, we develop solar cells using narrow bandgap organic cation-based PQDs and demonstrate substantially higher efficiency compared with their inorganic counterparts. We employ an alkyl ammonium iodide-based ligand exchange strategy, which proves to be substantially more efficient in replacing the long-chain oleyl ligands than conventional methyl acetate-based ligand exchange while stabilizing the α phase of organic PQDs in ambient conditions. We show a solar cell with the organic cation PQDs with high certified quasi-steady-state efficiency of 18.1% with 1,200-h stability under illumination at open-circuit conditions and 300-h stability at 80 °C.

尽管基于卤化铅钙钛矿的胶体量子点（PQD）已成为一种有前途的太阳能电池光活性材料，但迄今为止的研究主要集中在无机阳离子 PQD 上，尽管有机阳离子 PQD 具有更有利的带隙。在这项工作中，我们使用窄带隙有机阳离子 PQD 开发太阳能电池，并证明其效率比无机同类产品高得多。我们采用基于碘化烷基铵的配体交换策略，事实证明，与传统的基于乙酸甲酯的配体交换相比，该策略在替换长链油基配体方面要有效得多，同时在环境条件下稳定有机PQD 的α相。我们展示了一种采用有机阳离子 PQD 的太阳能电池，其经过认证的准稳态效率高达 18.1%，在开路条件下的光照下具有 1,200 小时的稳定性，在 80 °C 下具有 300 小时的稳定性。