Electro- and Cathodoluminescent Properties of ZnS:Cu,Mn and ZnS:Cu,Tb Thin Films

Abstract

The electroluminescent (EL) and cathodoluminescent (CL) characteristics of ITO-ZnS:Cu,Mn(Tb)-Al DC EL thin films were investigated. The experimental results showed that efficient resonant energy transfer takes place from self-activated ZnS and Cu centers to Mn ions resulting in high luminance of ZnS:Mn,Cu cells. EL properties of ZnS:Cu,Tb cells can be explained on the basis of the direct impact excitation model, while the energy transfer mechanism makes a negligible contribution to the excitation process. This accounts for the comparatively low EL luminance of Tb-doped cells.

Formation and Distinctive Decay Times of Surface- and Lattice-Bound Mn2+ Impurity Luminescence in ZnS Nanoparticles

“…The optical properties of transition-or lanthanide-metal ion-doped semiconductor nanoparticles have been extensively investigated recently. [13][14][15][16] Mn 2+ -doped ZnS nanoparticles especially have been extensively studied with interest, [17][18][19][20][21][22][23][24][25][26][27][28][29][30][31][32] as their efficient and characteristic luminescence might lead to a new class of luminescent materials in diverse applications such as displays, sensors, and lasers. 11, 14,29,30,33 It is well-known 21-23 that while undoped ZnS nanoparticles emit in the blue upon UV excitation, Mn 2+ -doped ones yield an orange emission band in addition to the blue band with significantly reduced emission intensity.…”

“…[13][14][15][16] Mn 2+ -doped ZnS nanoparticles especially have been extensively studied with interest, [17][18][19][20][21][22][23][24][25][26][27][28][29][30][31][32] as their efficient and characteristic luminescence might lead to a new class of luminescent materials in diverse applications such as displays, sensors, and lasers. 11, 14,29,30,33 It is well-known 21-23 that while undoped ZnS nanoparticles emit in the blue upon UV excitation, Mn 2+ -doped ones yield an orange emission band in addition to the blue band with significantly reduced emission intensity. The orange emission is known to result from the 4 T 1 f 6 A 1 transition of the Mn 2+ impurity excited via energy transfer from the ZnS host.…”

“…Nanoparticles have a variety of unique spectroscopic, electronic, and chemical properties that germinate from their quantum-confinement effects and high surface/volume ratios. − In particular, the optical properties of nanocrystalline metals ,− and semiconductors ,,− are of great interest in both basic and applied researches. The optical properties of transition- or lanthanide-metal ion-doped semiconductor nanoparticles have been extensively investigated recently. − Mn 2+ -doped ZnS nanoparticles especially have been extensively studied with interest, − as their efficient and characteristic luminescence might lead to a new class of luminescent materials in diverse applications such as displays, sensors, and lasers. ,,,, It is well-known 21-23 that while undoped ZnS nanoparticles emit in the blue upon UV excitation, Mn 2+ -doped ones yield an orange emission band in addition to the blue band with significantly reduced emission intensity. The orange emission is known to result from the 4 T 1 → 6 A 1 transition of the Mn 2+ impurity excited via energy transfer from the ZnS host. ,,− The short-decay time of Mn 2+ luminescence, together with its high quantum efficiency, is particularly important for applications where saturation limits the light output of a luminescent material.…”

Multicolor Tuning of Manganese-Doped ZnS Colloidal Nanocrystals

“…7,8 Among them, ZnS nanocrystals doped with transition metal ions such as Mn 2+ ions have been regarded as a promising new class of nanophosphors, owing to their superior luminescent properties and potential applications in displays, sensors, and lasers. [15][16][17][18] Therefore, it has stimulated many efforts to investigate the prepararion and properties of Mn 2+ -doped ZnS nanocrystals. [19][20][21][22][23][24] However, these as-synthesized Mn 2+ -doped ZnS nanocrystals usually suffered some problems such as poor quality of nanocrystals (e.g., irregular shape and wide size distribution) and limited tunable emission colors, which significantly hinders their potential applications.…”

Mn-doped ZnS nanoparticles as efficient low-voltage cathodoluminescent phosphors

“…The added Cu is thought to improve the energytransfer efficiency. 26 The voltage dependence of the nanoparticles' luminous efficiency provides some insight into the mechanism of the nearly universally observed loss of efficiency at voltages below 2 kV. In Fig.…”