Abstract The substitution of toxic lead (Pb) in efficient perovskite solar cells (PSCs) is a key problem for commercialization. In this paper, strontium chloride (SrCl2)-doped lead-less PSCs were constructed successfully, and the effect of Sr substitution on the perovskite film formation and its photovoltaic property was investigated in detail by X-ray diffraction (XRD), scanning electron microscopy (SEM), UV–visible absorption, time-resolved photoluminescence (TRPL), X-ray photoelectron spectroscopy (XPS) and electrochemical impedance spectroscopy (EIS) analyses. It is demonstrated that the introduction of Sr substitution changes the chemical composition of PbI2 precursors and reduces the excess PbI2 in the perovskite films. A 10 mol% Sr substitution in the PbI2 precursor solution can increase the absorbance of the resultant perovskite film and enhance the electron extraction at the “perovskite/TiO2” interface, thus increasing the device's short-circuit current density (Jsc) from 17.41 mA cm-2 to 19.45 mA cm-2. At the same time, Sr substitution can reduce the charge combination in the PSC, which allows the PSC to obtain a higher open-circuit voltage (Voc) of 1.08 V and fill factor (FF) of 0.74. Finally, the PSC prepared with 10 mol% Sr substitution exhibits a considerable power conversion efficiency (PCE) of 15.64%, showing an improvement of 18.9% compared to that of the pristine device.

中文翻译：

---

通过氯化锶替代提高光伏性能的无铅介观钙钛矿太阳能电池

摘要 在高效钙钛矿太阳能电池 (PSC) 中替代有毒铅 (Pb) 是商业化的关键问题。本文成功构建了氯化锶 (SrCl2) 掺杂的无铅 PSCs，并通过 X 射线衍射 (XRD)、扫描电子显微镜详细研究了 Sr 取代对钙钛矿薄膜形成及其光伏性能的影响。 (SEM)、紫外可见吸收、时间分辨光致发光 (TRPL)、X 射线光电子能谱 (XPS) 和电化学阻抗谱 (EIS) 分析。结果表明，Sr 取代的引入改变了 PbI2 前体的化学组成，并减少了钙钛矿薄膜中过量的 PbI2。PbI2 前驱体溶液中 10 mol% Sr 取代可以增加所得钙钛矿薄膜的吸光度并增强“钙钛矿/TiO2”界面处的电子提取，从而将器件的短路电流密度（Jsc）从 17.41 mA cm 增加-2 至 19.45 mA cm-2。同时，Sr 取代可以减少 PSC 中的电荷组合，这使得 PSC 获得 1.08 V 的更高开路电压 (Voc) 和 0.74 的填充因子 (FF)。最后，用 10 mol% Sr 取代制备的 PSC 表现出可观的功率转换效率 (PCE)，为 15.64%，与原始器件相比提高了 18.9%。同时，Sr 取代可以减少 PSC 中的电荷组合，这使得 PSC 获得 1.08 V 的更高开路电压 (Voc) 和 0.74 的填充因子 (FF)。最后，用 10 mol% Sr 取代制备的 PSC 表现出可观的功率转换效率 (PCE)，为 15.64%，与原始器件相比提高了 18.9%。同时，Sr 取代可以减少 PSC 中的电荷组合，这使得 PSC 获得 1.08 V 的更高开路电压 (Voc) 和 0.74 的填充因子 (FF)。最后，用 10 mol% Sr 取代制备的 PSC 表现出可观的功率转换效率 (PCE)，为 15.64%，与原始器件相比提高了 18.9%。