Luminescence and energy transfer processes in ensembles and single Mn or Tb doped ZnS nanowires

Abstract

Zinc sulfide (ZnS) nanowires with a typical diameter of 100 to 300 nm have been doped with different concentrations of either Mn or Tb using ion implantation. Both systems show very efficient and long living intra-shell luminescence with strong non-exponential decay characteristics in the range of milliseconds. The time behavior of the corresponding luminescence is well described within a modified Förster model, taking into account the lower dimensionality of the nanowires in case of radiationless dipole-dipole energy transfer. The general applicability of this model for energy transfer processes in low dimensional systems will be shown as a function of concentration, temperature, excitation density as well as for measurements on the level of single nanowires.

Intense Intrashell Luminescence of Eu-Doped Single ZnO Nanowires at Room Temperature by Implantation Created Eu–Oi Complexes

“…The detection was performed by a MS257 grating monochromator with an iStar intensified CCD (iCCD) camera. The gate width of the iCCD was varied between 1 μs for short times after excitation up to 1 ms for later times . Figure presents the temporal decay of the 5 D 0 → 7 F 2 emission in the ZnO nanowire matrix for samples, which were implanted to a concentration of 1 at.…”

Catalyst driven optical properties of the self – assembled ZnS nanostructures

“…14,15 The PL spectrum of undoped ZnS nanobelts and Mn doped ZnS nanobelts also showed some emission bands at 440 and 540 nm, which were assigned to defects produced by S and Zn vacancies, respectively, while the emission band observed at 590 nm in Mn doped ZnS was attributed to Mn d-d state transition. [16][17][18] It was also observed that the defect related emission decreased as Mn concentration increased in Mn-doped ZnS nanobelts. In the case of Cu-doped ZnS nanorods green emission was attributed to elemental S species present on the nanorod surface, and orange emission was associated with recombination of electrons at deep defect levels of Cu introduced states.…”