Carrier separation and transport in perovskite solar cells studied by nanometre-scale profiling of electrical potential. Journal Article uri icon

Overview

abstract

  • Organometal-halide perovskite solar cells have greatly improved in just a few years to a power conversion efficiency exceeding 20%. This technology shows unprecedented promise for terawatt-scale deployment of solar energy because of its low-cost, solution-based processing and earth-abundant materials. We have studied charge separation and transport in perovskite solar cells-which are the fundamental mechanisms of device operation and critical factors for power output-by determining the junction structure across the device using the nanoelectrical characterization technique of Kelvin probe force microscopy. The distribution of electrical potential across both planar and porous devices demonstrates p-n junction structure at the TiO2/perovskite interfaces and minority-carrier diffusion/drift operation of the devices, rather than the operation mechanism of either an excitonic cell or a p-i-n structure. Combining the potential profiling results with solar cell performance parameters measured on optimized and thickened devices, we find that carrier mobility is a main factor that needs to be improved for further gains in efficiency of the perovskite solar cells.

publication date

  • September 28, 2015

Full Author List

  • Jiang C-S; Yang M; Zhou Y; To B; Nanayakkara SU; Luther JM; Zhou W; Berry JJ; van de Lagemaat J; Padture NP

Other Profiles

Additional Document Info

start page

  • 8397

volume

  • 6