Designing lead-free inorganic perovskite or perovskite-like structure materials and researching the corresponding photoinduced charge carrier dynamics are always promising due to both the environment and power conversion efficiency considerations. In this work, we intelligently employ a bilayer metal Bi/Cu thin film with different atomic ratios as the precursor to fabricate a CuBiI₄ perovskite-like film in situ with a controlled Bi gradient at room temperature. This structure can significantly affect the photoinduced charge carrier dynamics of the resulting products. Next, a series of transient surface photovoltage (TSPV) measurements are carried out to investigate the photoinduced charge carrier dynamics of such CuBiI₄ and CuBiI₄:organic hybrid thin films. The results reveal that the gradually decreasing Bi content from ITO to CuBiI₄ can facilitate the photoinduced charge carrier transportation. Finally, a champion PCE of 1.10% is obtained for an ITO/CuBiI₄:polythieno[3,4-b]-thiophene-co-benzodithiophene (PTB7)/Au solar cell device. In particular, we find an exact negative correlation of the defined parameter L (the defined value for evaluating the photoinduced charge carrier dynamics in TSPV measurements) with the corresponding PCE of various devices for the first time, which may pave a new way for evaluating the potential photoelectric and photovoltaic performances of new materials without the assembly of solar cell devices.

中文翻译：

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CuBiI4基钙钛矿样太阳能电池的梯度形成和电荷载流子动力学

出于环境和功率转换效率的考虑，设计无铅无机钙钛矿或类钙钛矿结构材料并研究相应的光诱导电荷载流子动力学总是很有希望的。在这项工作中，我们智能地采用具有不同原子比的双层金属Bi / Cu薄膜作为前体，在室温下原位制备具有Bi受控梯度的CuBiI ₄钙钛矿状薄膜。该结构可显着影响所得产物的光诱导载流子动力学。接下来，进行了一系列瞬态表面光电压（TSPV）测量，以研究此类CuBiI ₄和CuBiI ₄的光诱导载流子动力学：有机混合薄膜 结果表明，Bi含量从ITO逐渐降低到CuBiI ₄可以促进光生载流子的迁移。最后，对于ITO / CuBiI ₄：聚噻吩并[3,4- b ]-噻吩-共-苯并二噻吩（PTB7）/ Au太阳能电池装置，获得了1.10％的最佳PCE 。特别是，我们首次发现了定义的参数L（用于评估TSPV测量中的光生电荷载流子动力学的定义值）与各种设备的相应PCE的确切负相关性，这可能为评估B的新方法铺平了道路。无需组装太阳能电池设备，即可获得新材料的潜在光电和光伏性能。