Far-Red Interlayer Excitons of Perovskite/Quantum-Dot Heterostructures

Taek Joon Kim, Sang hun Lee, Eunji Lee, Changwon Seo, Jeongyong Kim, Jinsoo Joo

Research output: Contribution to journalArticlepeer-review

4 Citations (Scopus)

Abstract

Interlayer excitons (IXs) at the interface of heterostructures (HSs) with a staggered band alignment are fascinating quantum quasi-particles with light-emitting and long-lifetime characteristics. In this study, the energy band alignments (EBAs) of the HS of MAPbI3 perovskite thin sheets with CdSe-ZnS core–shell quantum dot (QD) layers are modulated by using different diameters of the QDs. Far-red IX emission is observed at 1.42 eV from the HS of MAPbI3/CdSe-ZnS-QD (λem = 645 nm) with type-II EBA owing to charge transfer. The lifetime of the far-red IXs is estimated to be 5.68 µs, which is considerably longer than that (0.715 ns) of the intralayer excitons from CdSe-ZnS-QD. With increasing incident excitation power, the PL peak and its intensity of IXs are blue-shifted and linearly increased, respectively, indicating a strong dipole alignment of far-red IXs at the heterojunction. Back focal plane imaging suggests that the directions of dipole moments of the IXs are relatively out-of-plane compared to those of the intralayer excitons (MAPbI3 and CdSe-ZnS-QD). Notably, the abnormal behavior of the optical characteristics is observed near the phase transition temperature (90 K) of MAPbI3. MAPbI3/CdSe-ZnS-QD HS photodetectors show the increase in photocurrent and detectivity compared to MAPbI3 at IX excitation.

Original languageEnglish
Article number2207653
JournalAdvanced Science
Volume10
Issue number14
DOIs
Publication statusPublished - 2023 May 17

Bibliographical note

Publisher Copyright:
© 2023 The Authors. Advanced Science published by Wiley-VCH GmbH.

Keywords

  • charge transfer
  • far-red
  • interlayer exciton
  • optoelectronics
  • perovskite
  • quantum dots

ASJC Scopus subject areas

  • Medicine (miscellaneous)
  • General Chemical Engineering
  • General Materials Science
  • Biochemistry, Genetics and Molecular Biology (miscellaneous)
  • General Engineering
  • General Physics and Astronomy

Fingerprint

Dive into the research topics of 'Far-Red Interlayer Excitons of Perovskite/Quantum-Dot Heterostructures'. Together they form a unique fingerprint.

Cite this