Zhang Pengyun, Xiong Jie, Chen Wei-Hsiang, Du Pingfan, Song Lixin
College of Textile Science and Engineering, Zhejiang Sci-Tech University, Hangzhou, 310018, China.
School of Science, Huzhou University, Huzhou, 313000, Zhejiang, China.
Dalton Trans. 2023 Nov 7;52(43):15974-15985. doi: 10.1039/d3dt02080k.
In recent years, air-processed MAPbI perovskite solar cells (PSCs) have attracted widespread interest from researchers worldwide because of their simple and low-cost fabrication process. Nonetheless, the ambient conditions usually bring about many adverse effects, such as imperfect crystallization and numerous defects in perovskite films, which seriously impact both the photoelectric performance and stability of the device. Therefore, in this work, a polymer dual-passivation strategy was employed by introducing ammonium polyphosphate (APP) as an additive to the green anti-solvent to accurately modify the perovskite layer. APP, which has abundant phosphate and ammonium groups, could simultaneously fill the I/Pb vacancies by Lewis acid-base reactions to restrain defect formation and improve the power conversion efficiency (PCE) of the ultimate device. On the other hand, the long molecular chains of the polymer with a certain flexural ability were easily congregated at the grain boundaries of the perovskite grains, thus enhancing the bending resistance. Consequently, high-quality perovskite films with a dense morphology and large grain size were obtained. Because of the reduced defect density and suppressed non-radiative recombination, the optimal PSC attained a champion PCE of 20.87% with negligible hysteresis. Furthermore, the non-encapsulated APP-modified flexible device also exhibited excellent bending resistance. Only 20% of its normalized PCE was lost after 150 bending cycles at room temperature. This simple, green, low-cost, and reliable strategy for preparing high-efficiency PSCs with good stability can facilitate its commercialization.
近年来，气相法制备的甲脒铅碘（MAPbI）钙钛矿太阳能电池（PSC）因其制备工艺简单且成本低廉，受到了全球研究人员的广泛关注。尽管如此，环境条件通常会带来许多不利影响，例如钙钛矿薄膜结晶不完善以及存在大量缺陷，这严重影响了器件的光电性能和稳定性。因此，在本工作中，通过将聚磷酸铵（APP）作为添加剂引入绿色反溶剂中，采用了聚合物双钝化策略来精确修饰钙钛矿层。APP含有丰富的磷酸根和铵根基团，可通过路易斯酸碱反应同时填充碘/铅空位，抑制缺陷形成，提高最终器件的功率转换效率（PCE）。另一方面，具有一定挠曲能力的聚合物长分子链易于聚集在钙钛矿晶粒的晶界处，从而增强了抗弯曲能力。结果，获得了具有致密形态和大晶粒尺寸的高质量钙钛矿薄膜。由于缺陷密度降低且非辐射复合受到抑制，最优的PSC实现了20.87%的冠军功率转换效率，滞后现象可忽略不计。此外，未封装的APP修饰的柔性器件也表现出优异的抗弯曲性能。在室温下进行150次弯曲循环后，其归一化功率转换效率仅损失20%。这种制备具有良好稳定性的高效PSC的简单、绿色、低成本且可靠的策略有助于其商业化。
