Ligand-Induced Luminescence Transformation in AgInS2 Nanoparticles: From Defect Emission to Band-Edge Emission

CdS nanocrystals were synthesized by a solvent-thermal method in ethylenediamine at different temperature and time. The samples were investigated by XRD, TEM, Uv-vis absorption and PL spectroscopy. The solvent-thermal temperature at 200 °C is an optimal reaction temperature for preparing CdS nanorods with high crystallinity. The PL spectra exhibited two typical emissions: near band edge emission (centered at ~520nm) and defect emission (a broad peak in the range of 550-750nm). The defect emission decreased gradually and disappeared finally with the reaction time increasing from 1 to 12h, but the near band edge emission increased. This revealed that the quality of the CdS samples improved by degrees as the reaction time increased. The growth of single-crystalline CdS nanorods followed three steps; (a) CdS nuclei formed by reacting Cadmium chloride dihydrate and thiourea in ethylenediamine at 200 °C, (b) CdS nuclei grew into thin nanowhiskers after 1h reaction, (c) the growth of CdS nanorods based on nanowhiskers via a Ostwald ripening process.

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The Excitation Intensity Effect in the Band‐Edge Emission of GaAs and CdSe

Journal of Applied Physics ◽

10.1063/1.1655765 ◽

1968 ◽

Vol 39 (1) ◽

pp. 351-353 ◽

Cited By ~ 11

Author(s):

Jick H. Yee ◽

George A. Condas

Keyword(s):

Excitation Intensity ◽

Band Edge ◽

Band Edge Emission ◽

Edge Emission ◽

Intensity Effect

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Giant enhancement of ultraviolet near-band-edge emission from a wide-bandgap oxide with dipole-forbidden bandgap transition

Journal of Alloys and Compounds ◽

10.1016/j.jallcom.2017.02.119 ◽

2017 ◽

Vol 705 ◽

pp. 492-496 ◽

Cited By ~ 2

Author(s):

Hang Zhou ◽

Rui Deng ◽

Yongfeng Li ◽

Bin Yao ◽

Jieming Qin ◽

...

Keyword(s):

Wide Bandgap ◽

Band Edge ◽

Near Band Edge Emission ◽

Near Band Edge ◽

Band Edge Emission ◽

Edge Emission

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Core Nanoparticle Engineering for Narrower and More Intense Band-Edge Emission from AgInS2/GaSx Core/Shell Quantum Dots

Nanomaterials ◽

10.3390/nano9121763 ◽

2019 ◽

Vol 9 (12) ◽

pp. 1763 ◽

Cited By ~ 3

Author(s):

Watcharaporn Hoisang ◽

Taro Uematsu ◽

Takahisa Yamamoto ◽

Tsukasa Torimoto ◽

Susumu Kuwabata

Keyword(s):

Surface Passivation ◽

Precursor Solution ◽

Silver Sulfide ◽

Band Edge ◽

Crystal Phase ◽

Band Edge Emission ◽

Edge Emission ◽

Orthorhombic Crystal ◽

Metal Precursor ◽

Ag2s Nanoparticles

Highly luminescent silver indium sulfide (AgInS2) nanoparticles were synthesized by dropwise injection of a sulfur precursor solution into a cationic metal precursor solution. The two-step reaction including the formation of silver sulfide (Ag2S) nanoparticles as an intermediate and their conversion to AgInS2 nanoparticles, occurred during the dropwise injection. The crystal structure of the AgInS2 nanoparticles differed according to the temperature of the metal precursor solution. Specifically, the tetragonal crystal phase was obtained at 140 °C, and the orthorhombic crystal phase was obtained at 180 °C. Furthermore, when the AgInS2 nanoparticles were coated with a gallium sulfide (GaSx) shell, the nanoparticles with both crystal phases emitted a spectrally narrow luminescence, which originated from the band-edge transition of AgInS2. Tetragonal AgInS2 exhibited narrower band-edge emission (full width at half maximum, FWHM = 32.2 nm) and higher photoluminescence (PL) quantum yield (QY) (49.2%) than those of the orthorhombic AgInS2 nanoparticles (FWHM = 37.8 nm, QY = 33.3%). Additional surface passivation by alkylphosphine resulted in higher PL QY (72.3%) with a narrow spectral shape.

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Stable enhancement of near-band-edge emission of ZnO nanowires by hydrogen incorporation

Nanotechnology ◽

10.1088/0957-4484/21/6/065709 ◽

2010 ◽

Vol 21 (6) ◽

pp. 065709 ◽

Cited By ~ 53

Author(s):

A Dev ◽

R Niepelt ◽

J P Richters ◽

C Ronning ◽

T Voss

Keyword(s):

Zno Nanowires ◽

Band Edge ◽

Near Band Edge Emission ◽

Near Band Edge ◽

Band Edge Emission ◽

Edge Emission ◽

Hydrogen Incorporation

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Using dispersion theory to interpret the polarization properties of the band-edge emission in GaN crystals

Solid State Communications ◽

10.1016/0038-1098(87)90591-6 ◽

1987 ◽

Vol 61 (6) ◽

pp. 381-384

Author(s):

Bao Qingcheng ◽

Zhang Fengling ◽

Li Duolu ◽

Dai Rensong ◽

Xu Xurong

Keyword(s):

Band Edge ◽

Band Edge Emission ◽

Dispersion Theory ◽

Edge Emission

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Enhancement of Photoluminescence from Organic and Inorganic Surface Passivated ZnS Quantum Dots

MRS Proceedings ◽

10.1557/proc-667-g3.1 ◽

2001 ◽

Vol 667 ◽

Author(s):

Hatim Mohamed El-Khair ◽

Ling Xu ◽

Mingha Li ◽

Yi Ma ◽

Xinfan Huang ◽

...

Keyword(s):

Quantum Dots ◽

Organic Coating ◽

Band Edge ◽

Band Edge Emission ◽

Trap States ◽

Edge Enhancement ◽

Edge Emission ◽

Inorganic And Organic

ABSTRACTZnS quantum dots (QDs) chemically synthesized in PVP stabilizing medium have been coated with Zn(OH)2, SiO2and polystyrene (PS) shells as inorganic and organic passivation agents. to synthesize ZnS/Zn(OH)2, ZnS/SiO2and ZnS/PS QDs. PL properties of inorganically passivated ZnS/Zn(OH)2 and ZnS/SiO2 had reported band edge enhancement of 8-10 times, while organically passivated ZnS/PS QDs exhibit tremendous enhancement of band edge emission as much as 10-15 times,. Therefore inorganic and organic coating can passivate trap states of different energies on the surface of ZnS QDs.

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