Affiliation:
1. Department of Electronic Engineering College of Information Science and Technology Jinan University Guangzhou 510632 China
2. Institute of New Energy Technology College of Physics & Optoelectronic Engineering Jinan University Guangzhou 510632 China
3. Key Laboratory of New Semiconductors and Devices of Guangdong Higher Education Institutes Jinan University Guangzhou 510632 China
Abstract
In advancing high‐performance tin‐based perovskite solar cells, rapid crystallization and oxidation susceptibility are key challenges. SnF2, often added to control crystallization and oxidation, may impact cell performance, particularly postannealing. This study uses in situ variable‐temperature X‐Ray diffraction to examine SnF2's physicochemical behavior and phase transitions in these cells. The analysis highlights how residual SnF2 affects carrier recombination through energy‐level structures. Postfilm formation, SnF2 chemically interacts with 2,2′:6′,2″‐Terpyridine (TPY), forming a stannous fluoride complex that enhances electron transport and energy alignment. Crucially, TPY passivates surface defects and reduces tin vacancies, boosting device stability. The experimental results indicate that the unencapsulated devices in air atmosphere exhibit a stabilized power output retention rate above 90% of the initial efficiency after 29.5 h. After ≈800 h of continuous illumination in ambient air, the conversion efficiency can still be maintained above 100%. Remarkably, t90 (time to retain 90% efficiency) of the target device in pure oxygen is over 24 h.
Funder
National Natural Science Foundation of China
Natural Science Foundation of Guangdong Province
China Scholarship Council
Subject
Electrical and Electronic Engineering,Energy Engineering and Power Technology,Atomic and Molecular Physics, and Optics,Electronic, Optical and Magnetic Materials