Recent research has focused on increasing the open-circuit voltage (V_OC) and current density (J_SC) of perovskite solar cells (PSCs) by introducing p- or n-type dopants with higher electronegativity than Ti into the TiO₂ electron transport layer (ETL). However, these kinds of dopant create undesired charge traps that hinder charge transport through TiO_2. Therefore, the improvement in V_OC is often accompanied by an undesired current density–voltage (J–V) hysteresis problem. Herein, we demonstrate that the introduction of 4-chlorobenzoic acid (4-ClBA-TiO₂) dopant into TiO₂ not only overcomes the J–V hysteresis issue but also increases the V_OC, J_SC and power conversion efficiency (PCE) in mesoscopic PSCs. Also, the material shown the better device performance compared to the state-of-art ETL, with the 4-CLBA-TiO_2. We speculate that the interaction between the 4-ClBA and the perovskite interface is more selective for electrons. Further the 4-ClBA-TiO₂ electron mobility has been improved 1.9 times compared with TiO₂. As a result, for mesoscopic PSCs, the doping of 4-ClBA-TiO₂ increases the efficiency from 18.23% to 20.22%, while the hysteresis is largely reduced from 20.2% to 1.5%. To the best of our knowledge, this is the first report using the spin coating blocking layer to achieve over 20%. Thus, we believe that this approach will be an effective design strategy capable of enhancing the performance of PSCs with less hysteresis.

最近的研究集中在通过向TiO ₂电子传输层中引入电负性比Ti高的p型或n型掺杂剂来增加钙钛矿太阳能电池（PSC）的开路电压（V _OC）和电流密度（J _SC）。（ETL）。然而，这些种类的掺杂物的产生所不期望的电荷陷阱，通过二氧化钛阻碍电荷输送_2.因此，在改进V _OC常伴不希望的电流密度-电压（Ĵ-V ）磁滞问题。在这里，我们证明了将4-氯苯甲酸（4-ClBA-TiO ₂）掺杂剂引入TiO ₂不仅克服了J–V滞后问题，但也会增加介观PSC中的V _OC，J _SC和功率转换效率（PCE）。同样，与最新的ETL（4-CLBA-TiO _2）相比，该材料显示出更好的器件性能_。我们推测4-ClBA和钙钛矿界面之间的相互作用对电子更具选择性。此外，与TiO ₂相比，4-ClBA-TiO _2的电子迁移率提高了1.9倍。结果，对于介观的PSC，4-ClBA-TiO ₂的掺杂效率从18.23％降低到20.22％，而磁滞从20.2％大大降低到1.5％。据我们所知，这是首次使用旋涂阻挡层达到20％以上的报告。因此，我们认为这种方法将是一种有效的设计策略，能够以更少的磁滞来增强PSC的性能。