In this work we report a simple and cost‐effective CsPbBr₃‐based solar cell without ordinary selective contacts. To do so we follow an electrochemical approach consisting of three successive steps: (1) electrodeposition of PbO₂ directly on top of FTO substrates, (2) heterogeneous phase reaction with gaseous HBr and (3) spin‐coating of methanolic CsBr solutions followed by annealing. This method is more adequate for large‐scale environmentally friendly production as it reduces chemical waste, particularly toxic lead. The resulting films were structurally and optically characterized showing good coverage of the FTO substrates, absence of defects such as pinholes and orthorhombic structure. Photovoltaic and impedance characterization was carried out by pressing a carbon coated metal spring onto the CsPbBr₃ film until obtaining maximized open‐circuit potential (V_oc) and short‐circuit photocurrent density (j_sc) under simulated sunlight. The stabilized current at fixed voltage (SCFV) technique gave a maximum PCE value of 2.70 % close to devices with similar configuration. Impedance measurements demonstrated analogous behavior to that of state‐of‐art CsPbBr₃ based solar cells, comprising a recombination arc at mid‐high frequencies, geometrical capacitance and ideality factors closed to 2, typical of SRH recombination in the perovskite bulk.

中文翻译：

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无选择接触的CsPbBr3基太阳能电池的电化学辅助生长

在这项工作中，我们报告了一种简单且具有成本效益的基于CsPbBr ₃的太阳能电池，没有普通的选择性接触。为此，我们遵循由三个连续步骤组成的电化学方法：（1）电沉积PbO ₂（2）与气态HBr的异相反应，以及（3）甲醇CsBr溶液的旋涂，然后进行退火。这种方法更适合大规模的环境友好型生产，因为它减少了化学废物，特别是有毒铅。得到的膜在结构和光学上具有特征，显示出FTO基材的良好覆盖性，没有缺陷，例如针孔和正交结构。通过将碳涂层的金属弹簧压在CsPbBr ₃膜上直到获得最大的开路电势（V _oc）和短路光电流密度（j _sc）来进行光伏和阻抗表征）。固定电压（SCFV）技术下的稳定电流在具有类似配置的设备附近提供了2.70％的最大PCE值。阻抗测量显示出与基于CsPbBr _3的最新型太阳能电池相似的行为，包括中高频的复合电弧，几何电容和理想因数接近2的钙钛矿块体中的SRH重组。