Zhou Qin, Gao Yifeng, Cai Chunsheng, Zhang Zhuangzhuang, Xu Jianbin, Yuan Zhongyi, Gao Peng
CAS Key Laboratory of Design and Assembly of Functional Nanostructures, Fujian Provincial Key Laboratory of Nanomaterials Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou, Fujian, 350002, China.
Laboratory for Advanced Functional Materials, Xiamen Institute of Rare Earth Materials, Haixi Institute, Chinese Academy of Sciences, Xiamen, 361021, China.
Angew Chem Int Ed Engl. 2021 Apr 6;60(15):8303-8312. doi: 10.1002/anie.202017148. Epub 2021 Mar 4.
In recent years, the power conversion efficiency (PCE) of perovskite solar cells (PSCs) has witnessed rapid progress. Nevertheless, the pervasive defects prone to non-radiative recombination and decomposition exist at the surface and the grain boundaries (GBs) of the polycrystalline perovskite films. Herein, we report a comprehensive dual-passivation (DP) strategy to effectively passivate the defects at both surface and GBs to enhance device performance and stability further. Firstly, a fluorinated perylene-tetracarboxylic diimide derivative is permeated in the perovskite metaphase during antisolvent treatment, and then a fluorinated bulky aromatic ammonium salt is introduced over the annealed perovskite. The reduction of defect density can be unambiguously proved by the superoxide species generation/quenching reaction. As a result, optimized planar PSCs demonstrate a decreased open-circuit voltages deficit from 0.47 to 0.39 V and the best efficiency of 23.80 % from photocurrent scanning with a stabilized maximum power output efficiency of 22.99 %. Without encapsulation, one typical device can maintain over 85 % of the initial efficiency after heating on a hot plate at 100 °C for 30 h under relative humidity (RH) of 70 %. When the device is aged under 30±5 % RH, over 97 % of its initial PCE is retained after 1700 h.
近年来，钙钛矿太阳能电池（PSC）的功率转换效率（PCE）取得了快速进展。然而，多晶钙钛矿薄膜的表面和晶界（GB）存在普遍的缺陷，容易发生非辐射复合和分解。在此，我们报告了一种全面的双钝化（DP）策略，以有效钝化表面和GB处的缺陷，进一步提高器件性能和稳定性。首先，在反溶剂处理过程中，一种氟化苝四羧酸二亚胺衍生物渗透到钙钛矿中期，然后在退火后的钙钛矿上引入一种氟化大体积芳香铵盐。超氧物种的产生/猝灭反应可以明确证明缺陷密度的降低。结果，优化后的平面PSC的开路电压损失从0.47 V降至0.39 V，光电流扫描的最佳效率为23.80%，稳定最大功率输出效率为22.99%。在未封装的情况下，一个典型器件在相对湿度（RH）为70%的条件下于100 °C的热板上加热30 h后，仍可保持初始效率的85%以上。当器件在30±5 % RH下老化时，1700 h后仍保留其初始PCE的97%以上。
