Layers of compact nanostructured TiO2 were deposited by aerosol spray pyrolysis.
Crystallization of theTiO2 was observed with increasing deposition temperatures.
The sprayed-on TiO2 was used for the hole-blocking layer in a CH3NH3PbI3 solar cell.
Cross-sectional TEM images of the CH3NH3PbI3 solar cells were prepared by FIB.