Study of defect generated visible photoluminescence in zinc oxide nano-particles prepared using PVA templates

Oudhia, Anjali; Choudhary, Ankit; Sharma, Savita; Aggrawal, Sudiksha; Dhoble, S.J.

doi:10.1016/j.jlumin.2014.04.023

Cited by 11 publications

(5 citation statements)

References 65 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…This suggests that interfacial bonding between ZnO nanoparticles and CNT or PEDOT:PSS via OH groups plays an important role in excitonic separation and recombination. The probable origin of the DLE is the combination of several point defects, such as oxygen interstitials (O i ), oxygen vacancies (V O ), zinc vacancies (V Zn ), zinc interstitials (Zn i ), and their complexes [22,46] that are related to the presence of hydrates in the ZnO precursor. In addition, the NBE to DLE ratio is useful in evaluating the crystalline quality of ZnO.…”

Section: Optical Propertiesmentioning

confidence: 99%

Significance of Hydroxyl Groups on the Optical Properties of ZnO Nanoparticles Combined with CNT and PEDOT:PSS

et al. 2022

View full text Add to dashboard Cite

We report on the synthesis of ZnO nanoparticles and their hybrids consisting of carbon nanotubes (CNT) and polystyrene sulfonate (PEDOT:PSS). A non-aqueous sol–gel route along with hydrated and anhydrous acetate precursors were selected for their syntheses. Transmission electron microscopy (TEM) studies revealed their spherical shape with an average size of 5 nm. TEM also confirmed the successful synthesis of ZnO-CNT and ZnO-PEDOT:PSS hybrid nanocomposites. In fact, the choice of precursors has a direct influence on the chemical and optical properties of the ZnO-based nanomaterials. The ZnO nanoparticles prepared with anhydrous acetate precursor contained a high amount of oxygen vacancies, which tend to degrade the polymer macromolecule, as confirmed from X-ray photoelectron spectroscopy and Raman spectroscopy. Furthermore, a relative increase in hydroxyl functional groups in the ZnO-CNT samples was observed. These functional groups were instrumental in the successful decoration of CNT and in producing the defect-related photoluminescence emission in ZnO-CNT.

show abstract

Section: Optical Propertiesmentioning

confidence: 99%

Significance of Hydroxyl Groups on the Optical Properties of ZnO Nanoparticles Combined with CNT and PEDOT:PSS

et al. 2022

View full text Add to dashboard Cite

show abstract

“…Fig .6 shows the PL emission spectra of samples M 1 and M 2 prepared with varied molar ratio. A broad visible PL emission is observed centered on 477nm and 452nm corresponding to zinc interstitials (Zn••, Zn•) to valence band transition and 558, 531 nm corresponding to conduction to oxygen vacancy (Vo) transition respectively [3]. The sample M 1 with 2D structure exhibits higher PL intensity as compare to M 2 which has a 1D structure.…”

Section: Znomentioning

confidence: 98%

“…Concentration of OH -ions in the solution affects the hydrolysis process of ZnO formation, and hence it shows influence on morphology of material. We have already reported in our previous work [3], that growth unit (OH -) is responsible for growth of complex structures. Mostly nanomaterials are reported to be synthesized with special environment, sophisticated instruments and methods.…”

Section: Introductionmentioning

confidence: 93%

Pulsed Microwave Aided Morphology Controlled Synthesis of Nano Zinc Oxide

Choudhary¹,

Oudhia²

2016

IOSR

Self Cite

View full text Add to dashboard Cite

“…Лінії випромінювання в червоно -помаранчевій області з енергіями 2.17 еВ, 2.06 еВ, 1.88 еВ обумовлені, скоріше за все, переходами в межах нейтральних асоціативних центрів або з різними відстанями між донорами та акцепторами. Глибина залягання рівнів варіюється в [11] від 0.63 до 0.74 еВ в залежності від ширини забороненої зони зразків, а глибина залягання V O +2 становить порядку 0.6 еВ від дна зони провідності [12].…”

Section: рис 3 спектри фотолюмінесценції в уф-області зразки № 2 (1) ...unclassified

Nature of Zinc Oxide Colloidal Nanocrystals Photoluminescence

Nitsuk,

Huseynova,

Mamoilenko

et al. 2023

SEMST

View full text Add to dashboard Cite

The purpose of the study is to determine the nature of the radiative transitions responsible for the visible radiation of zinc oxide nanocrystals. Show that the size of nanocrystallites does not affect the spectral composition and location of long-wave luminescence. ZnO nanocrystals obtained by the method of colloidal synthesis with or without gelatin stabilization were investigated in the paper. The size of the nanocrystallites was determined in the approximation of the effective masses by the magnitude of the fundamental absorption edge shift. The results of calculating the size of nanocrystallites agree well with the results of SEM studies. It is shown that the main factor affecting the size of nanocrystallites is the concentration of precursors. Photoluminescence spectra of colloidal ZnO nanocrystals were studied in two spectral regions – ultraviolet and visible. Photoluminescence spectra in the ultraviolet region are characterized by three emission lines, the location of which depends on the concentration of precursors, that is, on the width of the band gap. Analysis of the energy states of intrinsic defects in nanostructured zinc oxide showed that the first two emission lines are associated with radiative transitions of excitons bound on neutral interstitial zinc atoms and on neutral zinc vacancies. The third line of ultraviolet radiation is caused by radiative transitions with the participation of deep donors, which are interstitial zinc atoms in the +2 charge state. The visible radiation spectra of colloidal ZnO nanocrystals are characterized by broad non-elemental emission bands in the blue-green and yellow-red regions of the spectrum. A detailed analysis of the spectra at different concentrations of precursors showed that the change in concentrations of precursors does not affect the spectral location of elementary emission lines. The absence of impurity absorption lines indicates that the centers responsible for visible radiation are donor-acceptor pairs. The analysis of the ratio of the emission lines intensities with increasing concentrations of the precursors shows that interstitial zinc and oxygen atoms dominate in the studied nanocrystals at high concentrations. As a result, in samples with a high concentration of precursors, blue radiation dominates over yellow and green. Thus, the study shows that by changing the concentrations of precursors, it is possible to influence both the spectral location of the edge ultraviolet luminescence and the intensity of individual long-wave luminescence components. The resulting colloidal ZnO nanocrystals can be used as luminescent sensors.

show abstract

Study of defect generated visible photoluminescence in zinc oxide nano-particles prepared using PVA templates

Cited by 11 publications

References 65 publications

Significance of Hydroxyl Groups on the Optical Properties of ZnO Nanoparticles Combined with CNT and PEDOT:PSS

Significance of Hydroxyl Groups on the Optical Properties of ZnO Nanoparticles Combined with CNT and PEDOT:PSS

Pulsed Microwave Aided Morphology Controlled Synthesis of Nano Zinc Oxide

Nature of Zinc Oxide Colloidal Nanocrystals Photoluminescence

Contact Info

Product

Resources

About