Incorporation of potassium halides in the mechanosynthesis of inorganic perovskites: feasibility and limitations of ion-replacement and trap passivation.

Potassium halides (KX; X = I, Br, or Cl) were incorporated as partial replacements of CsBr in the mechanosynthesis of CsPbBr 3 . This led to partial substitution of both monovalent ions forming mixed Cs 1- x K x PbBr 3- y X y perovskites. Longer photoluminescence lifetimes were also observed, possibly linked to the formation of a non-perovskite KPb 2 X 5 passivating layer.