A facile synthesis of highly water-soluble, core–shell organo-silica nanoparticles with controllable size via sol–gel process

Hollow inorganic particles have attracted considerable interest for a variety of applications. In this work, yeast powder was used as a bio-template to fabricate yeast/titania core-shell spheres. A titania precursor was deposited via the hydrolysis of tetraisopropyl titanate. Triethanolamine was employed to control the reaction rate of the sol-gel process. The hollow titania particles with a diameter of approximately 4 m and a thickness of approximately 54 nm were successfully obtained after calcination of the core-shell spheres at 700 °C. The crystal structure of the particles was anatase. The specific surface area and the average pore diameter were 21.4 m2/g and 1.6 nm, respectively. The photocatalytic activity of the hollow particles was higher compared with that of solid particles.

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Green and facile synthesis of high-quality water-soluble Ag-In-S/ZnS core/shell quantum dots with obvious bandgap and sub-bandgap excitations

Journal of Alloys and Compounds ◽

10.1016/j.jallcom.2018.04.242 ◽

2018 ◽

Vol 753 ◽

pp. 364-370 ◽

Cited By ~ 9

Author(s):

Yanyan Chen ◽

Qiang Wang ◽

Tianyong Zha ◽

Jigang Min ◽

Jingying Gao ◽

...

Keyword(s):

Quantum Dots ◽

Water Soluble ◽

Core Shell ◽

Facile Synthesis ◽

High Quality ◽

Quality Water

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Preparation and Characterization of Paclitaxel Imprinted Silica Nanoparticles

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.399-401.1894 ◽

2011 ◽

Vol 399-401 ◽

pp. 1894-1897

Author(s):

Jian Hua Li ◽

Zong Jian Zheng ◽

Shao Ping Fu ◽

Jing Bo Zhu

Keyword(s):

Silica Nanoparticles ◽

Dissociation Constants ◽

Sol Gel ◽

Scatchard Analysis ◽

Binding Properties ◽

Imprinted Polymers ◽

Sol Gel Process ◽

Equilibrium Dissociation Constants ◽

Equilibrium Dissociation

Highly selective molecularly imprinted layer-coated silica nanoparticles for paclitaxel were synthesized by molecular imprinting technique with a sol–gel process on the supporter of silica nanoparticles. The morphology of the obtained polymers was characterized by scanning electron microscopy (SEM). The binding properties of the imprinted polymers were evaluated through the equilibrium rebinding experiments. Scatchard analysis revealed that two classes of binding sites were formed in the imprinted polymers with equilibrium dissociation constants of 0.0509 g•L-1and 0.0094 g•L-1, respectively. Paclitaxel and its analogue were employed for selectivity tests. The results indicated that the imprinted polymers exhibited good selectivity and specificity toward paclitaxel.

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Characterization of Nanostructured Silica as Carrier for Insecticides Deltamethrin, Pyriproxyfen, and Chlorpyrifos and Testing the Insecticidal Efficacy Against Trogoderma granarium (Coleoptera: Dermestidae) Larvae

Journal of Economic Entomology ◽

10.1093/jee/toz264 ◽

2019 ◽

Vol 113 (1) ◽

pp. 511-517

Author(s):

Masumeh Ziaee ◽

Asgar Babamir-Satehi

Keyword(s):

Electron Microscopy ◽

Silica Nanoparticles ◽

Sol Gel ◽

Sem Analysis ◽

Efficient Treatment ◽

Trogoderma Granarium ◽

Transmission Electron ◽

Insecticidal Efficacy ◽

Sol Gel Process ◽

Nanostructured Silica

Abstract Nanostructured silica can be used as a carrier of pesticides to enhance stability and controlled release of agrochemicals with an effective concentration on target pests. Silica nanoparticles (SNPs) were synthesized by sol–gel process and employed as a carrier of three different insecticides including deltamethrin, pyriproxyfen, and chlorpyrifos. The SNPs were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM) analysis and the insecticides-loaded in SNPs were characterized by transmission electron microscopy (TEM). The toxicity of insecticides alone and loaded in SNPs was evaluated against small and large larvae of Trogoderma granarium Everts on concrete surfaces. The immediate mortality was counted after 1, 3, and 7 d of exposure, and then surviving individuals were transferred to untreated surfaces for seven more days, with delayed mortality was recorded. Small larvae were more susceptible than large ones on all insecticide treatments. In addition, insecticides loaded in silica nanoparticles were more effective when compared with application of the insecticides alone. For immediate mortality, deltamethrin loaded in SNPs was the most efficient treatment causing 70.5% mortality on small and 55.5% mortality on large larvae after 7 d of exposure to the highest concentration. Pyriproxyfen loaded in SNPs caused low immediate mortality, but the mortality increased in delayed count indicated that the insecticide could control the larvae even after they have been removed from treated surfaces. It can be concluded that loading insecticides in SNPs could significantly increase their insecticidal efficiency, but this increase was compound-dependent.

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Facile synthesis of ordered mesoporous silica with high γ-Fe2O3 loading via sol-gel process

Journal of Materials Science ◽

10.1007/s10853-008-2900-y ◽

2008 ◽

Vol 43 (18) ◽

pp. 6359-6365 ◽

Cited By ~ 13

Author(s):

Jiansheng Li ◽

Y. S. Lin

Keyword(s):

Mesoporous Silica ◽

Sol Gel ◽

Ordered Mesoporous Silica ◽

Facile Synthesis ◽

Ordered Mesoporous ◽

Sol Gel Process

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Effect of Cores on Photoluminescence of Hybrid SiO2-Coated CdTe Quantum Dots

Journal of Nanoscience and Nanotechnology ◽

10.1166/jnn.2020.17877 ◽

2020 ◽

Vol 20 (9) ◽

pp. 5478-5485

Author(s):

Cong Xie ◽

Yubin Zhao ◽

Yuxiang Song ◽

Yingjie Liu ◽

Yaya Wang ◽

...

Keyword(s):

Quantum Dots ◽

High Stability ◽

Sol Gel ◽

Quantum Yields ◽

Core Shell ◽

Aqueous Synthesis ◽

Pl Spectra ◽

Cdte Qds ◽

Sol Gel Process ◽

20 Nm

Compared with conventional semiconductor quantum dots, hybrid SiO2 coated CdTe QDs exhibited high stability, long fluorescent lifetime, high photoluminescence quantum yields, and well biocompatibility. In this paper, CdTe QDs with tunable PL from green to red emitting were prepared by an aqueous synthesis. A sol–gel process resulted in CdTe QDs coated with a hybrid SiO2 shell contained CdS-like clusters to obtain red-shifted PL spectra, increased PL efficiency and high stability. The clusters were formed by the reaction of Cd2+ and S2− ions generated via the decomposition of thioglycolic acid. The clusters around CdTe cores created a core–shell structure which is very similar with traditional semiconductor core–shell QDs. After being coated with a hybrid SiO2 shell, the PL of green-emitting naked CdTe QDs was red-shifted largely (~30 nm) while the PL of yellowemitting CdTe QDs revealed a small red-shifted (~20 nm). Furthermore, The PL of red-emitting naked CdTe QDs was red-shifted much small (less than 10 nm). This phenomenon is ascribed to the change of band gap of CdTe cores with sizes. The red-shift of PL spectra is attributed to the CdS-like clusters around the core rather than the thickness of the hybrid SiO2 shell.

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Synthesis and Characterization of SiO2@Y2MoO6:Eu3+ Core–Shell Structured Spherical Phosphors by Sol–Gel Process

Journal of Nanoscience and Nanotechnology ◽

10.1166/jnn.2016.11862 ◽

2016 ◽

Vol 16 (4) ◽

pp. 3914-3920 ◽

Cited By ~ 1

Author(s):

G. Z Li ◽

F. H Liu ◽

Z. S Chu ◽

D. M Wu ◽

L. B Yang ◽

...

Keyword(s):

Electron Microscopy ◽

Annealing Temperature ◽

Uv Light ◽

Sol Gel ◽

Spherical Shape ◽

Core Shell ◽

X Ray ◽

Transmission Electron ◽

Sol Gel Process ◽

Average Size

SiO2@Y2MoO6:Eu3+ core–shell phosphors were prepared by the sol–gel process. X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), field emission scanning electron microscopy (FESEM), energy-dispersive X-ray spectra (EDS), transmission electron microscopy (TEM), photoluminescence (PL) spectra as well as kinetic decays were used to characterize the resulting SiO2@Y2MoO6:Eu3+ core–shell phosphors. The XRD results demonstrated that the Y2MoO6:Eu3+ layers on the SiO2 spheres crystallized after being annealed at 700 °C and the crystallinity increased with raising the annealing temperature. The obtained core–shell phosphors have spherical shape with narrow size distribution (average size ca. 640 nm), non-agglomeration, and smooth surface. The thickness of the Y2MoO6:Eu3+ shells on the SiO2 cores could be easily tailored by varying the number of deposition cycles (70 nm for four deposition cycles). The Eu3+ shows a strong PL emission (dominated by 5D0–7F2 red emission at 614 nm) under the excitation of 347 nm UV light. The PL intensity of Eu3+ increases with increasing the annealing temperature and the number of coating cycles.

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