Phenyltrimethylammonium as an Interlayer Spacer for Stable Formamidinium-Based Quasi-2D Perovskite Solar Cells

• Published in: Electronic materials letters 2024, 20(6), , pp.791-798
• Main Authors: Gil, Bumjin, Kim, Jinhyun, Park, Byungwoo
• Format: Article
• Language: English
• Subjects: Cations; Characterization and Evaluation of Materials; Charge transport; Chemistry and Materials Science; Condensed Matter Physics; Crystal defects; Crystal structure; Interlayers; Materials Science; Nanotechnology; Nanotechnology and Microengineering; Optical and Electronic Materials; Optoelectronic devices; Original Article - Energy and Sustainability; Perovskites; Photovoltaic cells; Quaternary ammonium salts; Solar cells; Structural stability; Two dimensional analysis; 전자/정보통신공학
• ISSN: 1738-8090; 2093-6788
• DOI: 10.1007/s13391-024-00497-w

Quasi-2D perovskite materials possess great potential in improving the stability of perovskite solar cells due to their superior chemical and structural stableness compared to 3D counterparts. Here, commonly-used 3D formamidinum lead iodide (FAPbI 3 ) perovskite is alloyed by addition of quaternary cation phenyltrimethylammonium (PTMA) up to 33% ( n  = 5), which forms quasi-2D perovskite phase that acts beneficial to charge transport and stability. Since the detailed structural analyses regarding this quaternary ammonium salt is still lacking, we attempt to provide how the presence of 2D perovskite affects the crystal structure based on x-ray diffraction techniques. It is shown that PTMA cations directs FAPbI 3 to have textured orientation and reduced strains. This led to enhanced extraction of photogenerated carriers and reduced defects, making it promising material for solar cell applications. The champion device remains stable under 60 °C or 1 sun for 700 h, demonstrating its potential for optoelectronic devices requiring long-term stability. Graphical Abstract Highlights • PTMA can be successfully alloyed in FAPbI 3 up to ~ 33%. • PTMA-alloyed FAPbI 3 demonstrates reduced strains and more textured perovskite layer. • Addition of PTMA results in improved PL yield and reduced trap density. • Solar cells with PTMA-alloyed FAPbI 3 shows excellent stability under heat or light.