Spatial and temporal imaging of long-range charge transport in perovskite thin films by ultrafast microscopy.

ABSTRACT: Charge carrier diffusion coefficient and length are important physical parameters for semiconducting materials. Long-range carrier diffusion in perovskite thin films has led to remarkable solar cell efficiencies; however, spatial and temporal mechanisms of charge transport remain unclear. Here we present a direct measurement of carrier transport in space and in time by mapping carrier density with simultaneous ultrafast time resolution and ∼50-nm spatial precision in perovskite thin films using transient absorption microscopy. These results directly visualize long-range carrier transport of ∼220 nm in 2 ns for solution-processed polycrystalline CH3NH3PbI3 thin films. Variations of the carrier diffusion coefficient at the μm length scale have been observed with values ranging between 0.05 a

SUBMITTER: Guo Z 

PROVIDER: S-EPMC4557372 | biostudies-literature | 2015 Jun

REPOSITORIES: biostudies-literature