The two-dimensional Ruddlesden-Popper (RP) hybrid perovskite semiconductors have received extensive attention from researchers in this field because of their excellent stability and optoelectronic properties. Zhang Xu, Ph.D. candidate at Dalian Institute of Chemical Physics, Chinese Academy of Sciences Under the guidance of Liu Shengzhong, researcher of the silicon solar cell group (DNL1606) and Zhao Kui, professor of Shaanxi Normal University, new progress was made in the study of the crystallization kinetics of two-dimensional perovskite. Related research results were published in Advanced Materials. .
The research uses high-energy synchrotron radiation technology to track the phase transition behavior in the process of forming solid-state thin films by real-time tracking of the solution of two-dimensional perovskite precursors. The substrate temperature and solvent properties are studied for the two-dimensional perovskite crystallization kinetics. Phase purity, alignment of quantum wells, and the influence of photovoltaic performance. The researchers found that the orderliness of the purity and crystal orientation of the two-dimensional perovskite phase was reduced, mainly due to the formation of the intermediate state of the former 'drive-solvent'. The perovskite nucleation barrier is increased. Therefore, the nucleation and growth of the two-dimensional perovskite by the substrate is the key to the formation of high-quality perovskite films. The researchers used basal-induced crystallization to suppress the precursors. The formation of the solvent's intermediate state promotes the vertical orientation of the two-dimensional quantum wells, which makes them more thermodynamically stable, and further improves the purity of the crystal phase. The high-quality perovskite films can greatly improve the photoelectric conversion efficiency of solar cells. Therefore, this study provides a theoretical basis for the preparation of high-quality low-dimensional perovskite thin films and high-performance optoelectronic devices, which will help further promote perovskite solar cells. Application to the business.
The above research work was supported by the national key R&D program, the National Natural Science Foundation of China, the Central University Fund, the Ministry of Education '111 Introduction Program', the 'Thousand People's Program' project, and Cornell University's high-energy synchrotron radiation source.
