Sol-gel fabrication of Ag-Coated ZnO quantum dots nanocomposites with excellent photocatalytic activity

2021 ◽  
Vol 118 ◽  
pp. 111235
Author(s):  
Xinli Wang ◽  
Jin Li
Keyword(s):  
Quantum Dots ◽  
Photocatalytic Activity ◽  
Sol Gel ◽  
Excellent Photocatalytic Activity ◽  
Zno Quantum Dots

scholarly journals Microwave treated sol–gel synthesis and characterization of hybrid ZnS–RGO composites for efficient photodegradation of dyes

2017 ◽  
Vol 41 (4) ◽  
pp. 1723-1735 ◽  
Author(s):  
Lellala Kashinath ◽  
Keerthiraj Namratha ◽  
Shivanna Srikantaswamy ◽  
Ajayan Vinu ◽  
Kullaiah Byrappa
Keyword(s):  
Electron Transfer ◽  
Photocatalytic Activity ◽  
Sol Gel ◽  
Charge Recombination ◽  
Synthesis And Characterization ◽  
Excellent Photocatalytic Activity ◽  
Sol Gel Synthesis

Excellent photocatalytic activity by highly photo-responsive electron transfer from ZnS–RGO, and RGO acts as an electron reservoir and effectively suppresses charge recombination.

Photoluminescence of ZnO quantum dots produced by a sol–gel process

2008 ◽  
Vol 30 (8) ◽  
pp. 1233-1239 ◽  
Author(s):  
Debasis Bera ◽  
Lei Qian ◽  
Subir Sabui ◽  
Swadeshmukul Santra ◽  
Paul H. Holloway
Keyword(s):  
Quantum Dots ◽  
Sol Gel ◽  
Sol Gel Process ◽  
Zno Quantum Dots

Novel inorganic perovskite quantum dots for photocatalysis

Nanoscale ◽  
2017 ◽  
Vol 9 (33) ◽  
pp. 12032-12038 ◽  
Author(s):  
Ge Gao ◽  
Qiaoyue Xi ◽  
Hua Zhou ◽  
Yongxia Zhao ◽  
Cunqi Wu ◽  
...  
Keyword(s):  
Quantum Dots ◽  
Photocatalytic Activity ◽  
Room Temperature ◽  
Inorganic Perovskite ◽  
Excellent Photocatalytic Activity ◽  
Perovskite Quantum Dots ◽  
Highly Uniform

Uniform CsPbX3 quantum dots were synthesized via an emulsion fabrication and demulsion method at room temperature. The as-prepared CsPbX3 QDs exhibit high synthetic yield and highly uniform morphology, as well as excellent photocatalytic activity toward the degradation of MO.

Studies on Optical Properties of CdS/ZnO Quantum Dots Prepared by Sol-Gel Method

2011 ◽  
Vol 364 ◽  
pp. 129-133 ◽  
Author(s):  
Liyana Mohd Lawi Ruhana ◽  
Taqiyuddin Mawardi Ayob Muhammad ◽  
Radiman Shahidan ◽  
Irman Abdul Rahman ◽  
Bohari M. Yamin
Keyword(s):  
Quantum Dots ◽  
Sol Gel ◽  
Emission Spectra ◽  
Blue Shift ◽  
Mixture Ratio ◽  
Gel Method ◽  
Sol Gel Method ◽  
Transmission Electron ◽  
Zno Quantum Dots ◽  
Zno Qds

CdS/ZnO quantum dots (QDs) were prepared at a temperature of 293 K by the sol-gel method with Triethanolamine (TEA) as a capping agent. The effect of CdS/ZnO mixture ratio of 1:9, 1:1 and 9:1 on the optical absorption and fluorescence spectra were investigated by UV-Vis and Fluorescence spectroscopy. By increasing ZnO composition, a blue-shift of absorption edge and emission spectra were observed. The band gap for 1:9, 1:1 and 9:1 were found to be 4.13, 3.93 and 3.11 eV, respectively. The morphology of the CdS/ZnO QDs for each mixing ratio was obtained by transmission electron microscope (TEM). The size of the QDs was found to be in the range of 5-10 nm with some agglomerated particles.

Luminescence Properties of Sm3+/Eu3+ Co-Doped ZnO Quantum Dots

2016 ◽  
Vol 16 (4) ◽  
pp. 3597-3601
Author(s):  
Fengyi Liu ◽  
Hong Li ◽  
Yajing Hu ◽  
Na Jin ◽  
Yun Mou ◽  
...  
Keyword(s):  
Quantum Dots ◽  
Sol Gel ◽  
Spherical Shape ◽  
Hexagonal Wurtzite Structure ◽  
Luminescence Properties ◽  
Transmission Electron ◽  
Doped Zno ◽  
Zno Quantum Dots ◽  
Zno Qds ◽  
Co Doped

In order to improve luminescence properties of semiconductor ZnO quantum dots (QDs), Sm3+/Eu3+ co-doped ZnO QDs have been controllably synthesized by sol–gel method in this paper. ZnO QDs have a spherical shape with mean diameter at about 5–6 nm, which was characterized by high-resolution transmission electron microscopy (HRTEM). ZnO QDs have hexagonal wurtzite structure with parts of Sm3+ and Eu3+ incorporated into the lattice, which was demonstrated by X-ray Diffraction (XRD). Luminescence properties at room temperature (RT) of different amount of Sm3+ and 2 mol% Eu3+ doped ZnO QDs were examined in-depth by optical spectra. In contrast to the Pr3+/Eu3+ co-doped fluorescent performance researched in our previous study, the photoluminescence (PL) spectra indicates the unique luminescence properties of Sm3+/Eu3+ co-doped ZnO QDs. In addition, fluorescence lifetimes were obtained to illustrate the luminous mechanism.

Microstructure and Luminescence Properties of Tb3+ Doped ZnO Quantum Dots

2016 ◽  
Vol 16 (4) ◽  
pp. 3592-3596 ◽  
Author(s):  
Na Jin ◽  
Hong Li ◽  
Fengyi Liu ◽  
Ya-Hong Xie
Keyword(s):  
Quantum Dots ◽  
Surface Defects ◽  
Light Emission ◽  
Sol Gel ◽  
Spherical Shape ◽  
Hexagonal Wurtzite Structure ◽  
Quenching Effect ◽  
Doped Zno ◽  
Zno Quantum Dots ◽  
Zno Qds

In order to increase the exchange efficiency of solar cells by down-conversion, Tb3+ doped ZnO quantum dots (QDs) were successfully synthesized by sol–gel process. The X-ray diffraction (XRD) results indicate that ZnO QDs have hexagonal wurtzite structure. ZnO QDs have a spherical shape and diameter around 5 nm, which was confirmed by high-resolution transmission electron microscopy (HRTEM). The intensity of visible light emission peaks becomes strengthened and then weakened with the increase of Tb3+ doping concentration. When the concentration is more than 1%, because of the decrease of surface defects and concentration quenching effect, the emissive intensity is weakened. The enhancement of the PL emission peaks at 542 nm, 582 nm, and 619 nm was assigned to energy transfer between Tb3+ ions and ZnO QDs host. Moreover, the absorption spectra also demonstrates energy transfers from Tb3+ ions to ZnO QDs.

PHOTOCATALYTIC PROPERTY AND PHOTOCATALYTIC MECHANISM OF TiO2/Fe2O3 HYBRIDS FOR DEGRADATION OF ORGANIC DYES

2019 ◽  
Vol 26 (05) ◽  
pp. 1850196 ◽  
Author(s):  
CHUANSHENG CHEN ◽  
QUN FANG ◽  
SHIYI CAO ◽  
YONGXIANG YAN
Keyword(s):  
Photocatalytic Activity ◽  
Performance Enhancement ◽  
Organic Dyes ◽  
Sol Gel ◽  
Research Work ◽  
Photocatalytic Property ◽  
Ammonia Nitrogen ◽  
Solution Ph ◽  
Excellent Photocatalytic Activity ◽  
Potential Applications

In order to consider the performance enhancement and feasibility of practical application, this research work discussed the effects of different ions on the photocatalytic activity of TiO2/Fe2O3 hybrids in detail, involving H[Formula: see text], OH−, NH[Formula: see text], and NO[Formula: see text]. The TiO2/Fe2O3 hybrids were prepared by organic electrolyte-assisted sol–gel method under UV irradiation, and their function mechanisms were analyzed. Experiment results show that the resultant TiO2/Fe2O3 hybrids possess excellent photocatalytic activity and photocatalytic stability for degradation of organics under acid condition (pH 2–8). Notably, the NO[Formula: see text] ions could accelerate degradation of rhodamine B and methyl orange, and the recyclability of TiO2/Fe2O3 hybrids can be greatly enhanced in the co-existence of NO[Formula: see text] and NH[Formula: see text]. Meanwhile, this symbiosis of NO[Formula: see text] and NH[Formula: see text] is proven able to buffer the solution pH in photocatalysis. Furthermore, the prominent photocatalytic activity of TiO2/Fe2O3 hybrids for organic pollutants was mainly attributed to the formation of hydroxyl radicals (OH). The synthetic products show great potential applications in purification of air or wastewater that contains ammonia-nitrogen molecules.

scholarly journals Enhancement of Photocatalytic Activity by Mg2+ Doped Ceria Quantum Dots

2017 ◽  
Vol 2 (1) ◽  
Keyword(s):  
Quantum Dots ◽  
Photocatalytic Activity ◽  
Quantum Dot ◽  
Sol Gel ◽  
Lattice Parameter ◽  
Doped Ceria ◽  
X Ray Diffraction ◽  
X Ray ◽  
Gel Technique ◽  
Cubic Structure

The pure and Mg2+ doped CeO2 quantum dot were synthesized by sol-gel technique. The prepared quantum dots were characterized using X-ray diffraction pattern (XRD), Scanning electron microscope (SEM-EDX). The XRD results show cubic structure of the CeO2 quantum dots. The crystalline size (D), microstrain (ε), dislocation density (δ) and lattice parameter (α) were calculated and analyzed. SEM-EDX analysis shows the morphology and the presence of elements. The photocatalytic activity of the synthesized quantum dot was evaluated based on the photodegradation of methylene blue (MB) by UV-Vis spectrometry.

scholarly journals The Effects of Zinc Oxide (ZnO) Quantum Dots (QDs) Embedment on the Physicochemical Properties and Photocatalytic Activity of Titanium Dioxide (TiO2) Nanoparticles

2021 ◽  
Vol 32 (2) ◽  
pp. 71-85
Author(s):  
Anwar Iqbal ◽  
Usman Saidu ◽  
Farook Adam ◽  
Srimala Sreekantan ◽  
Normawati Jasni ◽  
...  
Keyword(s):  
Quantum Dots ◽  
Zinc Oxide ◽  
Titanium Dioxide ◽  
Physicochemical Properties ◽  
Quantum Confinement Effect ◽  
Sol Gel ◽  
Average Crystallite Size ◽  
Fluorescent Light ◽  
Zno Quantum Dots ◽  
Zno Qds

In this study, a detailed investigation on the effect of zinc oxide (ZnO) quantum dots (QDs) embedment on the physicochemical properties of anatase titanium dioxide (TiO2) was conducted. The highly porous nanocomposite labelled as ZQT was prepared via the sol-gel assisted hydrothermal method. The powder X-ray diffraction (XRD) analysis indicates that the average crystallite size of the ZnO QDs, anatase TiO2 (TiO2 NPs) and ZQT were 4.45 nm, 9.22 nm and 11.38 nm, respectively. Photoluminescent (PL) analysis detected the presence of defects related to TiO2, oxygen vacancies and quantum confinement effect (QCE) of the ZnO QDs in ZQT. These features enhanced the photodegradation of tetracycline (TC) under 48 watt of fluorescent light irradiation when ZQT (98.0%) was used compared to TiO2NPs (32.4%) and ZnO QDs (68.8%). The photodegradation activity was driven by O2●− followed by ●OH and h+.

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