Tuning luminescence of 3d transition- metal doped quantum particles: Ni+2: CdS and Fe+3: CdS

Abstract

The room-temperature photoluminescence of Cd 1−x M x S (M=Ni, Fe) nanoparticles were investigated. Compared with the photoluminescence of CdS which peaks at 475 nm, the photoemission of CdS:Fe nanoparticles was peaking at 537 nm because of Fe acting as luminescent centers. On the other hand, the green emission (503 nm) of CdS:Ni attributed to the 1 T 2g (D)→ 3 A 2g (F) raditive transition. With the increase of the Ni +2 concentration, photoluminescence intensity is increased while by Fe replacement with Cd ions, PL intensity is decreased. Relative to bulk crystals, due to the quantum confinement effect the band gap of CdS clusters is significantly blue-shifted with decreasing cluster size. CdS nanoclusters present a mixed hexagonal/cubic structure and with increasing doping concentration the peaks position of doped CdS shifts to higher angle.

Gallium‐Induced Perturbation of Zinc Selenide Quantum Dots Electronics

“…Based on this explanation, the absorption band of Ga‐doped ZnSe‐3MPA could be attributed to a blue shifted absorption edge of gallium‐doped ZnSe‐3MPA (if gallium is considered a p‐type dopant or an impurity), resulting from conduction band charging by the ionized electrons of the Ga 3+ dopant . These observations are consistent with previous explanations, that doping or the introduction of transition metal impurities into quantum dots changes the band gap values. The blue shift and broadening of the absorbance may also be due to stark effect arising from carrier filling of surface and trap states or introduction of above or below – gap energy states‐ as opposed to the core quantum dot states, all of which are dopant induced.…”

“…From the UV‐Vis absorption maximum (350 nm, equivalent to 3.54 eV), particle size can be calculated using the effective mass approximation model according to equation …”

Optical and structural properties of Ni2+-doped magnesium gallate polycrystalline samples

“…The optical properties of the Ni 2+ -doped materials have been studied since 1963 when the fluorescence and the optical maser oscillation in Ni 2+ :MgF 2 [8] was observed. Until the present day, several systems Ni 2+ -doped have been studied, with emission at visible and near infrared spectral regions [9][10][11][12][13][14]. In this paper we present photoluminescence data of Ni 2+ ions as substitutional impurities at the Mg 2+ sites in MgGa 2 O 4 (magnesium gallate).…”

Nickel and manganese‐doped CdS quantum dots: Optical study and photocatalytic activity on methylene blue

“…According to our previous works [17][18][19][20][21], typical doped Cd 0.97 SNi 0.03 QDs were prepared as follows: 1.5 mL of 0.05 M Ni-chloride and 48.5 mL of 0.05 M Cd-chloride were added into a 250-mL three-necked round-bottomed flask.…”

“…Photoluminescence Figure 6 shows the PL spectra of Mn 21 -doped CdS (1-7 at.%) QDs. As can be seen from Figure 6a, a broad blue emission band is observed around 487 nm which is attributed to the surface defect (S vacancy : V s ) [17,25]. Luminescence characteristics of nanosized doped ZnS:Mn 21 particles has been studied in our previous work [20].…”