Investigation on the high pressure annealing induced re-crystallization mechanism of CH3NH3PbI3 film

In this paper, high pressure annealing induced re-crystallization mechanism of CH3NH3PbI3 film has been investigated by SEM, UV–vis absorption spectra, and X-ray diffraction (XRD), respectively. CH3NH3PbI3 crystals, which were annealed under the pressure of 6 kPa at 100 °C for 80 min, were oriented at the same direction on the surface of the mesoporous Polypropylene (PP) film. These PP/CH3NH3PbI3 composite films exhibited different light-harvesting capabilities over the visible to near-IR. The evolution of the intensity ratio I110/I220 and I220/I310 of CH3NH3PbI3 annealed at 100 °C for different annealing time under the same pressure of 6 kPa has been also investigated in detail. Compared with the film prepared via the traditional method, the high pressure annealing induced CH3NH3PbI3 film showed better stability in moderate humid environmental condition (25% RH). [Display omitted] •Mesoporous polymer film was used to construct perovskite CH3NH3PbI3 thin film.•CH3NH3PbI3 crystals were oriented at the same direction on the surface of PP film.•High pressure annealing induced CH3NH3PbI3 films showed better stability property.