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RESEARCH PRODUCT
Quantifying the Composition of Methylammonium Lead Iodide Perovskite Thin Films with Infrared Spectroscopy
Robert LovrincicLidón Gil-escrigLidón Gil-escrigChristian MüllerSebastian BeckXiaokun HuangXiaokun HuangMichele SessoloAnnemarie PucciWolfgang KowalskyWolfgang KowalskyMichael Sendnersubject
Materials scienceInfraredAnalytical chemistryInfrared spectroscopyHalideSurfaces Coatings and FilmsElectronic Optical and Magnetic MaterialsGeneral EnergyEllipsometryPhysical and Theoretical ChemistryThin filmSpectroscopyChemical compositionPerovskite (structure)description
Lead halide perovskites (ABX3) are generally formed from a reaction of the lead halide salt (BX2) with the halide salt of the A cation (AX). The effects of varying film compositions as result of non-stoichiometric precursor ratios on electronic properties of halide perovskites are currently under debate. It is imperative, but experimentally challenging, to determine the chemical composition of thin films as a function of precursor ratio for a full understanding of the effect. Herein we report a precise quantification of the methylammonium (MA) content in differently fabricated films of MAPbI3 via infrared (IR) spectroscopy. We compare the thin film data to the first high quality dielectric function obtained from single crystals with IR ellipsometry. For spin-coated samples, we find that the MAI/PbI2 ratio in solution has an effect on the MA content in the resulting thin films which is in the range of 77-106% compared to single crystals. For co-evaporated samples, we show that a very similar range of MA co...
| year | journal | country | edition | language |
|---|---|---|---|---|
| 2019-08-19 | The Journal of Physical Chemistry C |