Quantification of Ionic Diffusion in Lead Halide Perovskite Single Crystals

Wei Peng, Clara Aranda, Osman Bakr, Germà Garcia-Belmonte, Juan Bisquert, Antonio Guerrero

Research output: Contribution to journalArticlepeer-review

127 Scopus citations

Abstract

Lead halide perovskites are mixed electronic/ionic semiconductors that have recently revolutionized the photovoltaics field. The physical characterization of the ionic conductivity has been rather elusive due to the highly intermixing of ionic and electronic current. In this work the synthesis of low defect density monocrystalline MAPbBr3 (MA=Methyl ammonium) solar cells free of hole transport layer (HTL) suppresses the effect of electronic current. Impedance spectroscopy reveals the characteristic signature of ionic diffusion (the Warburg element and transmission line equivalent circuit) and ion accumulation at the MAPbBr3/Au interface. Diffusion coefficients are calculated based on a good correlation between thickness of MAPbBr3 and characteristic diffusion transition frequency. In addition, reactive external interfaces are studied by comparison of polycrystalline MAPbBr3 devices prepared either with or without a HTL. The low frequency response in IS measurements is correlated with the chemical reactivity of moving ions with the external interfaces and diffusion into the HTL.
Original languageEnglish (US)
Pages (from-to)1477-1481
Number of pages5
JournalACS Energy Letters
Volume3
Issue number7
DOIs
StatePublished - May 25 2018

Fingerprint

Dive into the research topics of 'Quantification of Ionic Diffusion in Lead Halide Perovskite Single Crystals'. Together they form a unique fingerprint.

Cite this