Abstract: We studied the influence of surface morphology, crystal structure and optical absorption of the perovskite (CH₃ NH₃ PbI₃, MAPbI₃) films on the performance of the organic-inorganic hybrid perovskite solar cells which prepared by various sequential deposition technology. It is shown that deposition conditions have significant impacts on the morphologies of the MAPbI₃ adsorbent layers as well as the performance of the solar cells. Compared with the sequential MAI-soaking method, other deposition methods can effectively improve the morphology by increasing the flatness and full surface coverage. Meanwhile, the mechanism involved in the preparation of smooth, full-coverage MAPbI₃ films using the post-treatment method at room temperature (RT) was studied further. The results demonstrate that the resulting smooth MAPbI₃ thin films are virtually independent on the morphology of the raw perovskite films using various deposition methods, due to the formation and spreading of an intermediate MAPbI₃·MA liquid phase. These processes improved the morphology and crystallization of perovskite resulting in a significant enhancement in light absorption, photocurrent and the performance of solar cell devices.

Key words: deposition method, perovskite, morphology, photocurrent

摘要： 采用液相连续沉积法制备了有机/无机杂化钙钛矿（CH₃NH₃PbI₃，MAPbI₃）光吸收层，并研究了不同薄膜形貌、晶体结构和光吸收能力对钙钛矿太阳能电池性能的影响。结果表明：制备工艺对吸光层形貌和器件光电性能产生很大的影响。相对于分步浸渍法，分步旋涂法（分步旋涂无机相碘化铅PbI₂和有机相甲胺碘CH₃NH₃I前驱液）和气体辅助修复法（新制初始MAPbI₃薄膜在室温下置于甲胺气氛中）能有效改善薄膜形貌和平整度，获得覆盖完全的均匀钙钛矿吸光层。同时，进一步分析了初始MAPbI₃膜的形貌对气体修复法制备全覆盖平整钙钛矿薄膜的影响，发现初始钙钛矿膜的形貌对最终修复后的膜层形貌没有影响，这可能是因为不同初始MAPbI₃膜经甲胺气体处理后均形成一种"甲胺铅化碘-甲胺"（MAPbI₃·MA）的液态中间相，再经退火处理后均获得平整、致密的钙钛矿膜层，极大地提高了MAPbI₃的结晶度和薄膜均匀性，从而提高活性层的吸光率、光电流和电池效率。

关键词: 沉积法, 钙钛矿, 微观形貌, 光电流