The Role of the Organic Cation in Developing Efficient Green Perovskite LEDs Based on quasi‐2D Perovskite Heterostructures

Two dimensional/three-dimensional (2D/3D) metal halide perovskite heterostructures have gained significant attention in photovoltaic and LED applications. These heterostructures enhance device efficiency, yet their behavior remains partially understood. This study investigates the role of organic cations essential for forming 2D perovskite structures across various metal halide perovskite heterostructures. Efficient green perovskite LEDs are fabricated, revealing a strong correlation between cation content and performance. The study shows that crystalline 2D perovskite impedes electron injection, affecting device performance. Optimizing these heterostructures is critical for maximizing device efficiency, with future focus on enhancing charge-carrier injection into 2D perovskite structures.