Although the PbCl₂ has been exploited to improve the performance of perovskite solar cells, the mechanism of enhancement by the introducing PbCl₂ is not fully understudied. In present work, we used the PbCl₂ as a dopant to improve the perovskite film quality, we found the crystalline and grain size of perovskite film both increased with 10% molar ratio of PbCl₂. The in situ time-resolved grazing incidence wide-angle X-ray scattering measurements revealed that more pre-nucleated suspended in the solution when employed the PbCl₂ dopant, leading to high crystalline for perovskite film. An incorporation of the space charge limit current, photoluminescence, time-resolved photoluminescence measurements, we uncover the function of PbCl₂ in reduced trap density, decreased charge recombination and enhanced carrier lifetime. As a result, the efficiency of planar-structure perovskite solar cells based on PbCl₂ enhanced to as high as 19.79% with reduced hysteresis, increased by ∼23% compared to the device without PbCl₂ (16.05%). We believe that this work would provide a fundamental prospective for mixed perovskite and promote its application in perovskite photovoltaics.

尽管已经开发了PbCl ₂来改善钙钛矿太阳能电池的性能，但是尚未完全研究引入PbCl ₂的增强机理。在目前的工作中，我们使用PbCl ₂作为掺杂剂来改善钙钛矿薄膜的质量，我们发现钙钛矿薄膜的晶体和晶粒尺寸均随PbCl ₂摩尔比的增加而增加。原位时间分辨掠入射入射的广角X射线散射测量表明，使用PbCl ₂时，溶液中有更多的预成核悬浮物掺杂剂，导致钙钛矿薄膜具有高结晶度。结合空间电荷极限电流，光致发光，时间分辨的光致发光测量，我们发现了PbCl ₂在降低陷阱密度，降低电荷复合和延长载流子寿命方面的功能。结果，基于PbCl ₂的平面结构钙钛矿太阳能电池的效率提高了19.79％，滞后性降低，与没有PbCl ₂的器件相比提高了约23％（16.05％）。我们相信这项工作将为混合钙钛矿提供基本的前景，并促进其在钙钛矿光伏产品中的应用。