Fabrication of highly stable silica coated ZnCuInS nanocrystals monolayer via layer by layer deposition for LED application

In this study, non-toxic and highly stable silica coated ZnCuInS NCs were synthesized by a reverse microemulsion method. The single NCs were uniformly encapsulated in a silica shell with a diameter of ∼30nm. Although hydrolyzed TEOS caused a QY reduction, and a 12.5nm red shift occurred after silica coating, the photo and thermal stabilities were extremely improved. For LED application, the silica coated ZnCuInS NCs phosphor layer was arrayed on the InGaN LED surface by layer-by-layer deposition utilizing electrostatic attraction. When the ZnCuInS/SiO2 NCs single monolayer was fabricated, 6.73% high color conversion efficiency was achieved.