Effect of Zn2+ and Mn2+ introduction on the luminescent properties of colloidal ZnS:Mn2+ nanoparticles

We report the observation of photoluminescence (PL) enhancement and quenching for 580 nm emission following the variation of time decay patterns, induced by Zn2+ and Mn2+ introduction, respectively, in colloidal ZnS:Mn2+ nanoparticles (NPs). The activation and quenching processes are analyzed considering surface nonradiative relaxation based on the Langmuir isotherm and Poisson statistics, respectively. The PL enhancement is most likely related to the elimination of dangling bonds from the lone pairs on surface S2− anions. The results indicate that rich Zn2+ and poor Mn2+ in colloidal ZnS:Mn2+ NPs are the key to obtain highly efficient luminescence.

[1]  Y. Wang,et al.  Irradiation-induced luminescence enhancement effect of ZnS:Mn(2+) nanoparticles in polymer films. , 1997, Optics letters.

[2]  Shihua Huang,et al.  Luminescence enhancement of core-shell ZnS:Mn/ZnS nanoparticles , 2002 .

[3]  Nicholas J. Turro,et al.  Luminescent probes for detergent solutions. A simple procedure for determination of the mean aggregation number of micelles , 1978 .

[4]  Kaushik Patel,et al.  Q-CdS Photoluminescence Activation on Zn2+ and Cd2+ Salt Introduction , 2001 .

[5]  Zhong Lin Wang,et al.  Synthesis and photoluminescence enhancement of Mn2+-doped ZnS nanocrystals , 2000 .

[6]  R. W. Fessenden,et al.  Photoelectrochemistry in particulate systems. 6. Electron-transfer reactions of small cadmium sulfide colloids in acetonitrile , 1987 .

[7]  Horst Weller,et al.  Photochemistry of colloidal semiconductors. 20. Surface modification and stability of strong luminescing CdS particles , 1987 .

[8]  Alex V. Isarov and,et al.  Optical and Photochemical Properties of Nonstoichiometric Cadmium Sulfide Nanoparticles: Surface Modification with Copper(II) Ions , 1997 .

[9]  Mamoru Senna,et al.  Enhancement of photoluminescence of ZnS: Mn nanocrystals modified by surfactants with phosphate or carboxyl groups via a reverse micelle method , 2002 .

[10]  Gallagher,et al.  Optical properties of manganese-doped nanocrystals of ZnS. , 1994, Physical review letters.

[11]  Louis E. Brus,et al.  A simple model for the ionization potential, electron affinity, and aqueous redox potentials of small semiconductor crystallites , 1983 .

[12]  L. Brus,et al.  Electron-hole recombination emission as a probe of surface chemistry in aqueous cadmium sulfide colloids , 1982 .