Enhancing Chemical Bonding at Buried Interface Enables Improved Performance of Perovskite Solar Cell
Sicen Zhou, Hepeng Wang, Yuqing Luo, Zhouti Wang, Shiqing Ding, Yuecheng Hu, Jiangsheng Xie, Tianbao Yu, Pingqi Gao
Abstract
The buried interface plays a vital role in determining the performance and durability of perovskite devices since it influences the charge movement, defects at the interface, and the growth of crystals. However, the self-assembled monolayer (SAM) generally leads to poor contact due to the weak intermolecular interactions. Here, an effective co-assembly monolayer method is reported by incorporating acetyl dl-carnitine chloride (ACL) into [4-(3,6-dimethyl-9H-carbazol-9yl) butyl] phosphonic acid (Me-4PACz) ethanol solution. The application of the ACL improves the coverage of SAM and simultaneously enhances the chemical bonding at the buried interface. As a result, the perovskite solar cells achieve a power conversion efficiency of 25.78% under simulated AM1.5 light conditions, maintaining more than 90% of their original efficiency after ≈600 h of operation at peak power.