Continuous White Luminescence of ZnS:Pb²⁺ and Core/Shell ZnS:Pb²⁺/ZnS Nanocrystals

Abstract

High-quality water-soluble ZnS:Pb2+ nanocrystals were synthesized via a simple chemical codepositing method. The as-synthesized ZnS:Pb2+ nanocrystals show high monodispersity and crystallinity with a narrow size distribution (3.2 +/- 0.4 nm). ZnS:Pb2+/ZnS core/shell structures were also obtained by coating a ZnS shell displaying significantly enhanced photoluminescence (PL) intensity and photostability. For the ZnS:Pb2+/ZnS samples the position of emission spectrum shows a red-shift of approximately 10 nm, which produces a fairly pure white emission with Commission Internationale de l'Eclairage (CIE) coordinates of (0.31, 0.33). These phenomena are explained by a model of multiple Pb2+ luminescent centers.

Correlated Color Temperature Tunable White Electroluminescence from Cadmium-Free ZnS Quantum Dots

“…As a blue-light-emitting semiconductor, nanoscale ZnS prepared via convenient routes displays remarkable optical properties. [19][20][21] Photoluminescence (PL) spectra with various colors from defects of ZnS QDs were observed 19 22 23 and the PL quantum yield has reached as high as 31%. 19 So combined defects emission of ZnS QDs becomes a prospective method to accomplish white EL.…”

Efficient Infrared Luminescence of Er<SUB>2</SUB>S<SUB>3</SUB>/ZnS Core/Shell Quantum Dots and IR QDs-LED

“…Among these types, the doped semiconductor quantum dots can achieve light emissions with a broader spectrum by tuning the doping ion. The doped semiconductor quantum dots have been numerously investigated [14][15][16] because of their excellent performance. For instance, transition metal ions such as Mn 2+ , Cu 2+ , Co 2+ or rare earth ions such as Eu 3+ , Er 3+ , Tb 3+ were doped into II-VI semiconductor matrix like CdSe, CdS, ZnS, ZnSe, etc.…”