Multifunctional Guanidine Ionic Liquid with Lactate Anion-Assisted Crystallization and Defect Passivation for High-Efficient and Stable Perovskite Solar Cells

作者：A. Saeed, Liang Wang, Zhaoyang Chen, Junhui Fang, Lin Yuan, Shuai Wang, Iqbal Hussain, Jianwei Zhao, Qingqing Miao · 发表于：ACS Applied Energy Materials · 年份：2024 · DOI：10.1021/acsaem.4c01057 · 被引用次数：7 · 研究领域：Perovskite Materials and Applications、Conducting polymers and applications、Quantum Dots Synthesis And Properties

Perovskite solar cells (PSCs) are receiving tremendous attention among other photovoltaic devices for their high power conversion efficiency (PCE), facile fabrication technique, eco-friendliness, and low cost. Unfortunately, the intrinsic defects and the quality of the perovskite films arising from the halide ion migration and undercoordinated Pb 2+ are still considered to be the bottleneck for long-term operational stability. Herein, the introduction of task-specific ionic liquid (IL) tetramethylguanidine lactate (GuLAC) demonstrates excellent defect passivation effects and crystal growth. More specifically, the formation of hydrogen bonds between –NH 2 in GA + and I – passivates cation defects, while strong chemical interaction of lactate anion passivates the undercoordinated Pb 2+ . Both experimental observations and theoretical simulation confirm the strong interaction of GuLAC with the perovskite, which is responsible for restricting ion migration, improving grains’ size, and elongating the carrier lifetime. As a result, the IL-modified device exhibits improved PCE and superior long-term stability compared to the control device. The incorporation of IL additives proves to be a viable approach for achieving both high PCE and stable PSC devices.