In perovskite solar cells (PSCs), the interface defects between the perovskite active layer (PVK) and the electron transport layer (ETL) represent a primary constraint impacting both efficiency and stability. To modulate the buried interface, a multifunctional molecule of rubidium dihydrogen phosphate (RbDP) was inserted into the buried interface. To see clearly the situation and structure of the perovskite bottom layer and deeply understand the influence of the buried interface, the ETL/PVK is peeled off. Various electrochemical characterizations indicate that the modulation of RbDP effectively diminishes amorphous regions and defects, alleviates in-plane tensile strain, reduces defects at the buried interface and inside of perovskite, and facilitates the extraction and transportation of charge carriers. Thus, the power conversion efficiency (PCE) of RbDP-modified formamidinium-based PSCs was 24.52 %, over the pristine device's 22.04 %. Furthermore, the unencapsulated RbDP-based device retains an initial efficiency of 90 % after 150 days of follow-up testing in the humidity range of 40 ± 10 %.

中文翻译：

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磷酸二氢铷对高效钙钛矿太阳能电池的埋入界面调制


在钙钛矿太阳能电池（PSC）中，钙钛矿活性层（PVK）和电子传输层（ETL）之间的界面缺陷是影响效率和稳定性的主要约束。为了调节埋入界面，将磷酸二氢铷（RbDP）的多功能分子插入到埋入界面中。为了看清钙钛矿底层的情况和结构，深入了解埋入界面的影响，将ETL/PVK剥离。各种电化学特性表明，RbDP的调制有效地减少了非晶区和缺陷，减轻了面内拉伸应变，减少了钙钛矿埋入界面和内部的缺陷，并促进了电荷载流子的提取和传输。因此，RbDP 修饰的甲脒基 PSC 的功率转换效率 (PCE) 为 24.52%，高于原始器件的 22.04%。此外，在 40 ± 10% 的湿度范围内进行 150 天的后续测试后，未封装的基于 RbDP 的器件仍保持 90% 的初始效率。