Comment on "Resolving spatial and energetic distributions of trap states in metal halide perovskite solar cells"

Sandheep Ravishankar; Thomas Unold; Thomas Kirchartz

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arXiv · 2008.02892

Comment on "Resolving spatial and energetic distributions of trap states in metal halide perovskite solar cells"

Sandheep Ravishankar·Thomas Unold·Thomas Kirchartz

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Abstract

Ni et al. report minimum bulk trap densities of 10^11 cm-3 and 1-4 orders change in interfacial trap densities derived from drive-level capacitance profiling of lead halide perovskites. From basic electrostatic arguments, we show that such bulk trap densities cannot be resolved for a p-i-n perovskite solar cell for the reported layer thicknesses, while the apparent interfacial charge densities are a consequence of the geometrical capacitance and of charge injection into the perovskite layer.

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Sandheep Ravishankar, Thomas Unold, Thomas Kirchartz. 2020-08-06. Comment on "Resolving spatial and energetic distributions of trap states in metal halide perovskite solar cells". https://arxiv.org/abs/2008.02892

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