Fig. 1: Exciton behaviors and intra/interlayer structural characteristics of 2D RP perovskites.

a Schematic diagram of carrier dynamics in 2D RP perovskite with various excitonic features. The trapped excitons in 2D RP perovskites with distorted [PbI6] octahedra exhibit weak emission, which would transform to free excitons with strong emission by suppressing exciton trapping. With the reduction of exciton binding energy, the free excitons could further dissociate into free carriers, leading to high photocurrent. b Illustrations of the synergistic manipulation of the intra and interlayer structures towards more desirable excitonic properties of 2D RP perovskites (using the example of n = 2).