Potassium-doped organometal halide perovskite solar cells (PSCs) of more than 20% power conversion efficiency (PCE) without I-V hysteresis were constructed. The crystal lattice of the organometal halide perovskite was expanded with increasing of the potassium ratio, where both absorption and photoluminescence spectra shifted to the longer wavelength, suggesting that the optical band gap decreased. In the case of the perovskite with the 5% K⁺, the conduction band minimum (CBM) became similar to the CBM level of the TiO₂-Li. In this situation, the electron transfer barrier at the interface between TiO₂-Li and the perovskite was minimised. In fact, the transient current rise at the maximum power voltages of PSCs with 5% K⁺ was faster than that without K⁺. It is concluded that stagnation-less carrier transportation could minimise the I-V hysteresis of PSCs.

中文翻译：

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钙掺杂的有机金属卤化物钙钛矿制成的无磁滞钙钛矿太阳能电池。

构建了钾掺杂的有机金属卤化物钙钛矿型太阳能电池（PSC），其功率转换效率（PCE）超过20％，并且没有IV磁滞现象。有机金属卤化物钙钛矿的晶格随着钾比的增加而膨胀，吸收光谱和光致发光光谱都移向更长的波长，表明光学带隙减小。在钙钛矿含5％K ⁺的情况下，导带最小值（CBM）变得与TiO ₂ -Li的CBM相似。在这种情况下，TiO ₂ -Li与钙钛矿之间的界面处的电子转移势垒被最小化。实际上，瞬态电流在5％K ⁺的PSC的最大电源电压下会上升比没有K ^+的要快。结论是无停滞的载流子运输可以使PSC的IV滞后最小化。