Three-dimensional perovskite modulated by two-dimensional homologue as light-absorbing materials for efficient solar cells

摘要

Organic-inorganic hybrid halide perovskites are highly promising candidates for efficient photovoltaics, however, the long-term stability in ambient air still limits their further practical applications. Herein, the enhancement of both performance and stability of perovskite solar cells is reported by employing two-dimension (2D)/three-dimension (3D) planar perovskite films. The 2D/3D planar perovskites combine the advantages of the high-performance from the 3D perovskite and the stability from 2D-perovskite. It is found that the benefits of the 2D perovskite are attributed to ultrathin coverage on the 3D perovskite surface, which not only passivates the grain boundaries of the underlayer 3D perovskite, but also aligns the energy level between the perovskite and hole transport layers from a microscopic point of view. This work demonstrates that modulating 2D/3D planar films by hybridizing different species of perovskite is a feasible way to simultaneously enhance both efficiency and stability of perovskite solar cells.