@article{SandbergKurpiersStolterfohtetal.2020,
  author    = {Sandberg, Oskar J. and Kurpiers, Jona and Stolterfoht, Martin and Neher, Dieter and Meredith, Paul and Shoaee, Safa and Armin, Ardalan},
  title     = {On the question of the need for a built-in potential in Perovskite solar cells},
  series = {Advanced materials interfaces},
  volume    = {7},
  journal   = {Advanced materials interfaces},
  number    = {10},
  publisher = {Wiley},
  address   = {Hoboken},
  issn      = {2196-7350},
  doi       = {10.1002/admi.202000041},
  pages     = {8},
  year      = {2020},
  abstract  = {Perovskite semiconductors as the active materials in efficient solar cells exhibit free carrier diffusion lengths on the order of microns at low illumination fluxes and many hundreds of nanometers under 1 sun conditions. These lengthscales are significantly larger than typical junction thicknesses, and thus the carrier transport and charge collection should be expected to be diffusion controlled. A consensus along these lines is emerging in the field. However, the question as to whether the built-in potential plays any role is still of matter of some conjecture. This important question using phase-sensitive photocurrent measurements and theoretical device simulations based upon the drift-diffusion framework is addressed. In particular, the role of the built-in electric field and charge-selective transport layers in state-of-the-art p-i-n perovskite solar cells comparing experimental findings and simulation predictions is probed. It is found that while charge collection in the junction does not require a drift field per se, a built-in potential is still needed to avoid the formation of reverse electric fields inside the active layer, and to ensure efficient extraction through the charge transport layers.},
  language  = {en}
}