Wang Sanlong, Qi Shanshan, Sun Hongrui, Wang Pengyang, Zhao Ying, Zhang Xiaodan
Institute of Photoelectronic Thin Film Devices and Technology, Renewable Energy Conversion and Storage Center, National Key Laboratory of Photovoltaic Materials and Solar Cells, Nankai University, Tianjin, China, 300350.
Angew Chem Int Ed Engl. 2024 May 6;63(19):e202400018. doi: 10.1002/anie.202400018. Epub 2024 Mar 28.
Inorganic perovskite solar cells (IPSCs) have gained significant attention due to their excellent thermal stability and suitable band gap (~1.7 eV) for tandem solar cell applications. However, the defect-induced non-radiative recombination losses, low charge extraction efficiency, energy level mismatches, and so on render the fabrication of high-efficiency inverted IPSCs remains challenging. Here, the use of 3-amino-5-bromopyridine-2-formamide (ABF) in methanol was dynamically spin-coated on the surface of CsPbIBr film, which facilitates the limited etching of defect-rich subsurface layer, resulting in the formation of vertical PbI nanosheet structures. This enabled localized contacts between the perovskite film and the electron transport layer, suppress the recombination of electron-hole and beneficial to electron extraction. Additionally, the C=O and C=N groups in ABF effectively passivated the undercoordinated Pb at grain boundaries and on the surface of CsPbIBr film. Eventually, we achieved a champion efficiency of 20.80 % (certified efficiency of 20.02 %) for inverted IPSCs with enhanced stability, which is the highest value ever reported to date. Furthermore, we successfully prepared p-i-n type monolithic inorganic perovskite/silicon tandem solar cells (IPSTSCs) with an efficiency of 26.26 %. This strategy provided both fast extraction and efficient passivation at the electron-selective interface.
无机钙钛矿太阳能电池（IPSCs）因其出色的热稳定性以及适用于串联太阳能电池应用的带隙（约1.7 eV）而备受关注。然而，缺陷诱导的非辐射复合损失、低电荷提取效率、能级不匹配等问题使得高效倒置IPSCs的制备仍然具有挑战性。在此，将3-氨基-5-溴吡啶-2-甲酰胺（ABF）在甲醇中的溶液动态旋涂在CsPbIBr薄膜表面，这有助于对富含缺陷的次表层进行有限蚀刻，从而形成垂直的PbI纳米片结构。这使得钙钛矿薄膜与电子传输层之间形成局部接触，抑制电子-空穴复合并有利于电子提取。此外，ABF中的C=O和C=N基团有效地钝化了CsPbIBr薄膜晶界处和表面上配位不足的Pb。最终，我们实现了倒置IPSCs的最高效率为20.80%（认证效率为20.02%），且稳定性增强，这是迄今为止报道的最高值。此外，我们成功制备了效率为26.26%的p-i-n型单片无机钙钛矿/硅串联太阳能电池（IPSTSCs）。该策略在电子选择性界面处实现了快速提取和高效钝化。
