Yue Tong, Li Kang, Li Xing, Ahmad Nafees, Kang Hui, Cheng Qian, Zhang Yingyu, Yue Yaochang, Jing Yanan, Wang Boxin, Li Shilin, Chen Jieyi, Huang Gaosheng, Li Yanxun, Fu Zihao, Wu Tong, Zafar Saud Uz, Zhu Lina, Zhou Huiqiong, Zhang Yuan
School of Chemistry, Beijing Advanced Innovation Center for Biomedical Engineering, Beihang University, Beijing 100191, People's Republic of China.
CAS Key Laboratory of Nanosystem and Hierarchical Fabrication, CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology, Beijing 100190, People's Republic of China.
ACS Nano. 2023 Aug 8;17(15):14632-14643. doi: 10.1021/acsnano.3c01908. Epub 2023 Jul 20.
Quasi-two-dimensional (2D) perovskites are highly promising light-harvesting materials for commercialization of perovskite solar cells (PSCs) owing to the excellent materials stability. However, the coexistence of multiple -value species in 2D perovskites often causes increased complexities in crystallization that can negatively affect the eventual photovoltaic performance. Herein, we present a binary solution based strategy via introducing nontoxic and widely accessible CHCOOH (HAc) as a co-solvent for preparing high-quality 2D perovskite films. Based on a 2D perovskite model system, (AA)MAPbI ( = 5), we show that the prenucleation and grain growth kinetics are appreciably modified with HAc, which benefits from the strong electron-donating ability of HAc with the key component of PbI, leading to formation of favorable cluster aggregates and resultant modulation of crystal growth. With the HAc-based method, the devices yield a boosted photovoltaic efficiency of 18.55% with an impressive photovoltage of 1.26 V. The champion cells exhibit a supreme thermal stability, showing <3% efficiency degradation under continuous thermal aging for 800 h.
准二维（2D）钙钛矿由于其出色的材料稳定性，是钙钛矿太阳能电池（PSC）商业化极具前景的光捕获材料。然而，二维钙钛矿中多值物种的共存常常会导致结晶过程中复杂性增加，这可能会对最终的光伏性能产生负面影响。在此，我们提出了一种基于二元溶液的策略，通过引入无毒且易于获取的CHCOOH（HAc）作为共溶剂来制备高质量的二维钙钛矿薄膜。基于二维钙钛矿模型体系（AA）MAPbI（ = 5），我们表明，预成核和晶粒生长动力学因HAc而得到明显改变，这得益于HAc与PbI的关键成分具有很强的给电子能力，从而导致形成有利的簇聚集体并对晶体生长进行调控。采用基于HAc的方法，器件的光伏效率提高到了18.55%，光电压达到了令人印象深刻的1.26 V。冠军电池表现出极高的热稳定性，在连续热老化800小时后效率降解小于3%。
