The role of mid-gap states in all-inorganic CsPbBr3 nanoparticle one photon up-conversion

Abstract

CsPbBr₃ nanoparticles that have been treated with NH₄SCN to produce essentially trap-free surfaces show an increase of one photon up-conversion quantum yield with little change to the up-conversion energy of activation, as estimated using an Arrhenius analysis. This suggests that mid-gap trap states constitute a loss pathway, and may not be integral to the one-photon excitation mechanism.