Determination of the True Lateral Grain Size in Organic-Inorganic Halide Perovskite Thin Films.
Gordon A MacDonaldChelsea M HeveranMengjin YangDavid MooreKai ZhuVirginia L FergusonJason P KillgoreFrank W DelRioPublished in: ACS applied materials & interfaces (2017)
In this letter, methylammonium lead iodide (MAPbI3) thin films were examined via piezoresponse force microscopy (PFM) and nanoindentation (NI) to determine if long-range atomic order existed across the full width and depth of the apparent grains. From the PFM, the piezoelectric response of the films was strongly correlated with low-index planes of the crystal structure and ferroelastic domains in macroscale solution-grown MAPbI3 crystals, which implied long-range order near the top surface. From the NI, it was found that the induced cracks were straight and extended across the full width of the apparent grains, which indicated that the long-range order was not limited to the near-surface region, but extended through the film thickness. Interestingly, the two MAPbI3 processes examined resulted in subtle differences in the extracted electro-mechanical and fracture properties, but exhibited similar power conversion efficiencies of >17% in completed devices.
Keyphrases
- room temperature
- crystal structure
- optical coherence tomography
- single molecule
- high speed
- diffusion weighted imaging
- high glucose
- high resolution
- ionic liquid
- diabetic rats
- metal organic framework
- water soluble
- high throughput
- perovskite solar cells
- solid phase extraction
- molecularly imprinted
- magnetic resonance imaging