In this study of the fabricated perovskite solar cells, flowing nitrogen is introduced during the spin coating of the precursor to remove the solvent vapor. The precursor is then aged prior to the anneal to obtain a pinhole-free perovskite film. Both the nitrogen flow and precursor aging methods resulted in improved film quality. The phase composition and orientation of the CH3NH3PbI3 phase was tuned through control of the aging time. This lead to high-performance CH3NH3PbI3 planar perovskite solar cells with power conversion efficiency over 16%. The intermediate phase composition was sensitive to the ambient atmosphere. The content of the PbI2 in the final CH3NH3PbI3 films varied with precursor aging time. The combination of nitrogen flow and suitable aging time resulted in films with enhanced (110)-orientation, compactness, charge carrier lifetimes, and correspondingly power conversion efficiencies.
- Intermediate phase
- Lead halide
- Solar cells
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Renewable Energy, Sustainability and the Environment
- Surfaces, Coatings and Films