Pan Yongyan, Wang Jianan, Sun Zhenxing, Zhang Jiaqi, Zhou Zheng, Shi Chenyang, Liu Sanwan, Ren Fumeng, Chen Rui, Cai Yong, Sun Huande, Liu Bin, Zhang Zhongyong, Zhao Zhengjing, Cai Zihe, Qin Xiaojun, Zhao Zhiguo, Ji Yitong, Li Neng, Huang Wenchao, Liu Zonghao, Chen Wei
Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology, Luoyu Road 1037, Wuhan, 430074, China.
Optics Valley Laboratory, Hubei, 430074, China.
Nat Commun. 2024 Aug 26;15(1):7335. doi: 10.1038/s41467-024-51703-0.
All-perovskite tandem solar cells have shown great promise in breaking the Shockley-Queisser limit of single-junction solar cells. However, the efficiency improvement of all-perovskite tandem solar cells is largely hindered by the surface defects induced non-radiative recombination loss in Sn-Pb mixed narrow bandgap perovskite films. Here, we report a surface reconstruction strategy utilizing a surface polishing agent, 1,4-butanediamine, together with a surface passivator, ethylenediammonium diiodide, to eliminate Sn-related defects and passivate organic cation and halide vacancy defects on the surface of Sn-Pb mixed perovskite films. Our strategy not only delivers high-quality Sn-Pb mixed perovskite films with a close-to-ideal stoichiometric ratio surface but also minimizes the non-radiative energy loss at the perovskite/electron transport layer interface. As a result, our Sn-Pb mixed perovskite solar cells with bandgaps of 1.32 and 1.25 eV realize power conversion efficiencies of 22.65% and 23.32%, respectively. Additionally, we further obtain a certified power conversion efficiency of 28.49% of two-junction all-perovskite tandem solar cells.
全钙钛矿串联太阳能电池在突破单结太阳能电池的肖克利-奎塞尔极限方面展现出了巨大潜力。然而，全钙钛矿串联太阳能电池的效率提升在很大程度上受到了Sn-Pb混合窄带隙钙钛矿薄膜中表面缺陷诱导的非辐射复合损失的阻碍。在此，我们报告了一种表面重构策略，该策略利用表面抛光剂1,4-丁二胺以及表面钝化剂乙二胺二碘化物来消除与Sn相关的缺陷，并钝化Sn-Pb混合钙钛矿薄膜表面的有机阳离子和卤化物空位缺陷。我们的策略不仅能提供具有接近理想化学计量比表面的高质量Sn-Pb混合钙钛矿薄膜，还能将钙钛矿/电子传输层界面处的非辐射能量损失降至最低。结果，我们制备的带隙分别为1.32和1.25 eV的Sn-Pb混合钙钛矿太阳能电池的功率转换效率分别达到了22.65%和23.32%。此外，我们还进一步获得了双结全钙钛矿串联太阳能电池28.49%的认证功率转换效率。
