Temperature dependence of the luminescence of nanocrystalline CdS/Mn2+

Abstract

The temperature dependence of the luminescence properties of nanocrystalline CdS/Mn 2þ particles is investigated. In addition to an orange Mn 2þ emission around 585 nm a red defect related emission around 700 nm is observed. The temperature quenching of both emissions is similar (T q < 100 K). For the defect emission the reduction in the lifetime follows the temperature dependence of the intensity. For the Mn 2þ emission however, the intensity decreases more rapidly than the lifetime with increasing temperature. To explain these observations a model is proposed in which the Mn 2þ ions are excited via an intermediate state involving shallowly trapped (< 40 meV) charge carriers. q

Doped Semiconductor Nanocrystals: Synthesis, Characterization, Physical Properties, and Applications

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“…In one such study (82), the doped CdS nanocrystals were prepared by simple mixing of ethylene glycol solutions of cadmium and manganese acetate with a solution of sodium sulfide, followed by washing with methanol and thermal treatment in triethyl phosphate to deagglomerate the particles. Mean Conduction band (1) (2) (6) [Adapted from (122).] diameters of $2.4 nm were determined by X-ray diffraction measurements.…”

Synthesis route and optical characterization of CdS:Mn/polyvinyl alcohol nanocomposite

“…We ascribe the Mn-related emission to the d d  transitions of Mn 2+ ions. It is known that the d-d-transitions in manganese ions are forbidden; however, in crystals they can be excited via the energy transfer from the host lattice to Mn ions [22][23][24]. The spectral position of the Mn d d  -band in nanocrystals depends on the surrounding crystalline field.…”

Photoluminescence, thermoluminescence and Raman studies of CdS nanocrystalline phosphor

“…Thus, works on doped or alloyed nanocrystals are mainly devoted to tuning the optical and electronic properties of nanocrystals. To our knowledge, reports on Mn 2+ and Eu 3+ doped CdS nanophosphors are available [20][21][22], but Bi 3+ doped cadmium sulfide nanophosphors have been largely ignored. It was, therefore, decided to investigate the effects of Bi 3+ as a dopant on the photoluminescent and thermoluminescent properties of CdS nanoparticles.…”