The document reports on various characterization techniques used to analyze the material properties of perovskite thin films and solar cells, including X-ray diffraction, scanning electron microscopy, atomic force microscopy, absorption spectroscopy, photoluminescence spectroscopy, X-ray photoelectron spectroscopy, current density-voltage measurements, and external quantum efficiency measurements.

1. X-ray diffraction (XRD) profiles of perovskites show the main diffraction peaks

2. Low- and high-magnification scanning electron microscope (SEM) micrographs
of the top surface of perovskite films deposited on a glass substrate

3. Atomic force microscope (AFM) topographic 3D images of the surface of 2μm ×
2μm films

4. Absorption coefficient (α) as a function of wavelength for perovskite

5. The Dependence of the skin depth upon the photon energy of perovskites

6. Variation of the optical density, OD as a function of the photon energy for
perovskites

7. Urbach energies extracted from absorbance measurements (UV-Vis) plotted
against the bandgap

8. Optical absorbance spectrum for perovskite, perovskite with Spiro-OMeTAD
and perovskite with P3HT

9. Optical transmission spectrum for perovskite, perovskite with Spiro-OMeTAD
and perovskite with P3HT

10. UV-vis absorbance and PL spectra of perovskite thin films

11. Fluorescence Lifetime Imaging

12. Time resolution photoluminescence (TRPL) analysis of perovskite films

13. X-ray photoelectron spectroscopy (XPS) survey spectra of perovskite films
documented for I 3d5/2, and Pb 4f7/2

14. 3D structure and device fabrication processes of planar perovskite solar cell with
mixed cation solution processing

15. Current density vs voltage (J–V) curves from forward and reverse scans of mixed-
cation planar PSCs based on (a) spin-coated TiO2 with a thickness of 60–65 nm
and (b) spin-coated SnO2 as an electron-transport layer

16. External quantum efficiency and the integrated current density of the
perovskite solar cells

17. Current density vs voltage (J–V) curves in the dark for different thicknesses of
blocking layer with (a) semi logarithmic scale to identify the recombination
mechanism and (b) natural-log scale to calculate the diode ideality factors (n)
(the lines are fitted to the Shockley diode equation)

18. Histogram of PCE measured from 30 mixed cation based devices, which shows
an average PCE of a) 13.5% with TiO2 and b) 15.7% with SnO2