Visualization of Ion Migration in an Inorganic Mixed Halide Perovskite by One-Photon and Multiphoton Absorption: Effect of Guanidinium A-Site Cation Incorporation

Po Kai Kung, Kuang I. Lin, Chun Sheng Wu, Ming Hsien Li, Chia Ru Chan, Raja Rajendran, Chen Fu Lin, Peter Chen

Research output: Contribution to journalArticlepeer-review

5 Citations (Scopus)

Abstract

In this work, we present the ion migration of CsPbIBr2 under illumination and impede it by incorporating the large cations of guanidinium (GA). A series of "probe-set-probe"operations are applied to assess the photoluminescence (PL) behavior spectrally and spatially, which is correlated to the ion migration-induced phase separation, of CsPbIBr2 and GAxCs1-xPbIBr2 perovskites. The local lattice distortion introduced by GA could reduce the strain gradient in GAxCs1-xPbIBr2 to inhibit the ion migration, leading to a stable PL spectrum and enhanced device stability under light stimulation. A solar cell with an optimized stoichiometric composition of GA0.1Cs0.9PbIBr2 delivers comparable photovoltaic performance and improved stability compared to those of CsPbIBr2-based perovskite solar cells, retaining 80% of its initial power conversion efficiency after being continuously bathed in light for 8 h under ambient conditions without encapsulation, while the CsPbIBr2 counterpart shows an efficiency that is <30% of its initial value under the same test condition.

Original languageEnglish
Pages (from-to)6944-6955
Number of pages12
JournalJournal of Physical Chemistry Letters
Volume13
Issue number30
DOIs
Publication statusPublished - 2022 Aug 4

All Science Journal Classification (ASJC) codes

  • General Materials Science
  • Physical and Theoretical Chemistry

Fingerprint

Dive into the research topics of 'Visualization of Ion Migration in an Inorganic Mixed Halide Perovskite by One-Photon and Multiphoton Absorption: Effect of Guanidinium A-Site Cation Incorporation'. Together they form a unique fingerprint.

Cite this