Dong Zhuo, Wang Jiaduo, Men Jiao, Zhang Junwei, Wu Jinpeng, Lin Yuan, Xie Xiaoying, Wang Jiajun, Zhang Jingbo
Tianjin Key Laboratory of Structure and Performance for Functional Molecules, College of Chemistry, Tianjin Normal University, Tianjin 300387, China.
Beijing National Laboratory for Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China.
Inorg Chem. 2024 Mar 25;63(12):5709-5717. doi: 10.1021/acs.inorgchem.4c00178. Epub 2024 Mar 14.
The electron transport layer (ETL) plays an important role in determining the conversion efficiency and stability of perovskite solar cells (PSCs). Here, TiO thin film was prepared by irradiating diisopropoxy diacetylacetone titanium precursor thin film with 172 nm vacuum ultraviolet (VUV) at a low temperature. The prepared TiO thin film has higher electron mobility and conductivity. As it is used as an ETL for MAPbI PSCs, its band structure is better matched with the perovskite, and at the same time, due to the good interface contact, more uniform perovskite crystals are formed. Most importantly, a large number of hydroxyl radicals were formed during VUV irradiation of the precursor film, which made up for the oxygen defect present on the surface of the TiO thin film, and were adsorbed to the film surface. These hydroxyl groups form hydrogen bonds with methylammonium (MA) components on the MAPbI buried surface, thus promoting the transfer of photogenerated electrons at the MAPbI/ETL interface. The power conversion efficiency of PSCs fabricated in air with the ETL prepared by VUV irradiation is 20.46%, which is higher than that of the contrast solar cell based on the sintered ETL (17.96%).
电子传输层（ETL）在决定钙钛矿太阳能电池（PSC）的转换效率和稳定性方面起着重要作用。在此，通过在低温下用172 nm真空紫外线（VUV）辐照二异丙氧基二乙酰丙酮钛前驱体薄膜制备了TiO薄膜。所制备的TiO薄膜具有更高的电子迁移率和电导率。当它用作MAPbI PSC的ETL时，其能带结构与钙钛矿更好地匹配，同时，由于良好的界面接触，形成了更均匀的钙钛矿晶体。最重要的是，在前驱体薄膜的VUV辐照过程中形成了大量的羟基自由基，弥补了TiO薄膜表面存在的氧缺陷，并吸附在薄膜表面。这些羟基与MAPbI埋入表面上的甲铵（MA）成分形成氢键，从而促进了MAPbI/ETL界面处光生电子的转移。在空气中制备的具有VUV辐照制备的ETL的PSC的功率转换效率为20.46%，高于基于烧结ETL的对比太阳能电池（17.96%）。
