Deep red emission from Cs4PbI6/CsPbI3/ZnS heterostructure for enhanced stability and photoluminescence quantum yield

Inorganic halide perovskites have been regarded as fancy materials for the lighting and bio-medicine industry due to their wondrous photo-physical features. However, the instability concerns restrict their usage to some extent. Here, we demonstrated deep red emission from Cs4PbI6/CsPbI3/ZnS heterostructure by using a typical hot injection process. The as-obtained Cs4PbI6/CsPbI3/ZnS heterostructure carries deep red emission at 679 nm, with remarkably high photoluminescence quantum yield greater than 90%, longer carrier lifetime, and enhanced structural stability. The improved optical features and structural stability have been accredited to the complementary passivation of the halide vacancies and uncoordinated lead species of CsPbI3 by the 0D Cs4PbI6/ZnS and the formation of PbS even at a relatively low synthesizing temperature. Thus, this proposed heterostructure has the potential to be used in different displays and medical applications.