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DOE OSTI · 1601528

Correctly Assessing Defect Tolerance in Halide Perovskites

Zhang, Xie·Turiansky, Mark E.·Van de Walle, Chris G.
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Abstract

The notion of “defect tolerance” has often been invoked to explain the excellent performance of halide perovskites in optoelectronic applications. However, this concept has not been rigorously defined or assessed. A common interpretation is that all of the energetically favorable intrinsic defects are shallow. On the basis of examples in the prototypical halide perovskite CsPbI 3 , we show that this is not the case. The antisite defects Pb I and I Pb are energetically favorable, but also have levels deep in the band gap. Still, because of strong anharmonicity, they are not efficient nonradiative recombination centers. Here, our study demonstrates how to correctly evaluate the “defect tolerance” of halide perovskites.

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37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRYDefect toleranceDefectsEnergy levelsFirst-principles calculationsHalide perovskitesNonradiative recombinationPerovskitesPotential energyRecombination

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Zhang, Xie, Turiansky, Mark E., Van de Walle, Chris G.. 2020-02-25. Correctly Assessing Defect Tolerance in Halide Perovskites. https://doi.org/10.1021/acs.jpcc.0c01324

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