Extremely efficient internal exciton dissociation through edge states in layered 2D perovskites

Academic Article

Abstract

  • Understanding and controlling charge and energy flow in state-of-the-art semiconductor quantum wells has enabled high-efficiency optoelectronic devices. Two-dimensional (2D) Ruddlesden-Popper perovskites are solution-processed quantum wells wherein the band gap can be tuned by varying the perovskite-layer thickness, which modulates the effective electron-hole confinement. We report that, counterintuitive to classical quantum-confined systems where photogenerated electrons and holes are strongly bound by Coulomb interactions or excitons, the photophysics of thin films made of Ruddlesden-Popper perovskites with a thickness exceeding two perovskite-crystal units (>1.3 nanometers) is dominated by lower-energy states associated with the local intrinsic electronic structure of the edges of the perovskite layers. These states provide a direct pathway for dissociating excitons into longer-lived free carriers that substantially improve the performance of optoelectronic devices.
  • Published In

  • Science  Journal
  • Digital Object Identifier (doi)

    Author List

  • Blancon JC; Tsai H; Nie W; Stoumpos CC; Pedesseau L; Katan C; Kepenekian M; Soe CMM; Appavoo K; Sfeir MY
  • Start Page

  • 1288
  • End Page

  • 1292
  • Volume

  • 355
  • Issue

  • 6331