Efficiency promotion has been severely constrained by charge recombination in perovskite solar cells (PSCs). Interface modification has been proved to be an effective way to reduce the interfacial charge recombination. In this work, a mesoporous TiO₂ (mp-TiO₂) layer was modified by an ultrathin BaTiO₃ layer to suppress charge recombination in PSCs. The ultrathin BaTiO₃ modification layer was prepared by the spin coating method using a barium salt solution. The concentration of the barium salt solution was optimized, and the effect of the BaTiO₃ modification layer on the performance of the cells was also investigated. The modification layer can not only successfully retard charge recombination but also effectively boost the rate of electron extraction at the interface, resulting in enhanced open-circuit voltage (V_oc), short circuit current density (J_sc), and fill factor. Furthermore, the hysteresis of the PSCs was also significantly reduced after the modification. By optimizing and employing the BaTiO₃ modification layer, the power conversion efficiency of the cells was increased from 16.13 to 17.87%.

中文翻译：

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通过超薄BaTiO ₃界面改性增强钙钛矿太阳能电池的性能

钙钛矿型太阳能电池（PSC）中的电荷重组已严重限制了效率的提高。界面修饰已被证明是减少界面电荷重组的有效方法。在这项工作中，通过超薄BaTiO ₃层修饰了介孔TiO ₂（mp-TiO ₂）层，以抑制PSC中的电荷复合。使用钡盐溶液通过旋涂法制备超薄BaTiO ₃改性层。优化钡盐溶液的浓度，并优化BaTiO _3的作用还研究了修饰层对电池性能的影响。改性层不仅可以成功地阻止电荷复合，而且可以有效地提高界面处的电子提取速率，从而提高开路电压（V _oc），短路电流密度（J _sc）和填充系数。此外，修改后，PSC的磁滞也显着降低。通过优化和使用BaTiO ₃改性层，电池的功率转换效率从16.13％提高到17.87％。