Heteroepitaxial Growth to Construct Hexagonal/Hexagonal β‐NaYF4:Yb,Tm/Cs4PbBr6 Multi‐Code Emitting Core/Shell Nanocrystals

Synthesis of upconversion nanoparticles (UCNPs)-metal halide perovskites (MHPs) heterostructure is garnered immense attentions due to their unparalleled photophysical properties. However, the obvious difference in their structural forms makes it a huge challenge. Herein, hexagonal β-NaYF