- 标题
- 摘要
- 关键词
- 实验方案
- 产品
-
Fabrication of Remarkably Bright QD Densely-Embedded Silica Nanoparticle
摘要： We developed a synthesis method for silica-coated quantum dot (QD)-densely-embedded silica nanoparticle (Si@D-QD@Si NP) with remarkably brighter fluorescence by increasing the number of QDs on silica NPs. Si@D-QD@Si NPs exhibited a narrow size distribution and a high signal reproducibility. Red, green, and blue Si@D-QD@Si NPs were successfully fabricated and characterized. The Si@D-QD@Si NP carried 2.4 times more QDs than previously reported silica-coated QD-embedded silica NP (Si@QD@Si NP). The quantum yield of Si@D-QD@Si NPs was slightly higher than Si@QD@Si NPs. The red Si@D-QD@Si NPs showed approximately 26.6%, the green Si@D-QD@Si NP 36.2%, and the blue Si@D-QD@Si NP 39.3% higher fluorescence intensity compared to the corresponding Si@QD@Si NPs. This result implied that the particles can be used at bio-field with a higher sensitive detection.
关键词： Quantum dot,Quantum yield,Fluorescence,Silica coating,Silica nanoparticle
更新于2025-09-23 15:23:52
-
Oxidation/reduction control of the VO2 nanoparticle in the nano-confined space of the hollow silica nanoparticle
摘要： Vanadium dioxide (VO2) exhibits a good thermochromic property which can be used in a smart window. To improve its poor visible transparency, immobilization of the VO2 nanoparticles on the silica shell of hollow nanoparticles was proposed. In addition to improving the particle dispersibility of the VO2 and to reducing stress from repeated phase transitions of the VO2 between monoclinic and tetragonal, the hollow interior can reduce any undesirable oxidation of the VO2 to V3O7, V2O5, etc., along with the thermal decomposition behavior of organic compounds around the vanadium atom. The hollow silica nanoparticles with micropores (less than 2 nm) were prepared by a previously-reported template method. Through the pores, the vanadium precursor with a chelate ligand solution penetrates into the hollow interior. The vanadium intermediate formed by adding water was then captured by the silica shell. During the crystallization process under a nitrogen atmosphere, 10-30 nm of VO2 particles were immobilized on the silica shell with a high dispersibility by optimization of the vanadium precursor concentration, and ratios of vanadium/water and vanadium/hollow silica nanoparticles. The VO2/hollow silica nanoparticles in water exhibited a higher visible transparency than that of the commercial VO2. In addition, their thermochromic property in the infrared region was close to that of the commercial one.
关键词： Thermochromic,Hollow silica nanoparticle,Vanadium dioxide,Micropore
更新于2025-09-23 15:23:52
-
Influence of the parameters in the preparation of silica nanoparticles from biomass and chemical silica precursors towards bioimaging application
摘要： Silica nanoparticles (SNP’s) occupy a prominent role in scientific research due to their easy preparation methodology and its wide uses in various applications. In this work, SNP’s were prepared from biomass (rice husk) and chemical precursor, tetraethoxysilane (TEOS) with the particle sizes of 50 nm and 200 nm respectively. The influence of particle size on varying the concentration of ethanol and water in Stober method of synthesis were also analysed. Since, porphyrin has the good electro and photo catalytic property, in this study, porphyrin NP’s was functionalized on the surface of the SNP’s. The functional groups were confirmed from FTIR spectra. From SEM analysis, it was observed that, the size of the SNP’s increased with increase in the concentration of ethanol. The optical dynamic properties of SNP’s functionalized with porphyrin NP’s were analysed from UV-Vis spectroscopy and Fluorolog. Further, the functionalization of SNP’s and their binding affinity were calculated by UV absorption spectra.
关键词： Porphyrin,Rice husk,photoluminescence,Silica nanoparticle
更新于2025-09-10 09:29:36
-
Defect-induced Fluorescence of Silica Nanoparticles for Bioimaging Applications
摘要： With biocompatibility, biodegradability, and high functionality, silica nanoparticles (SNPs) have been widely investigated for various biomedical applications. However, lack of optical fluorescence has limited the application of SNPs as a degradable imaging agent. Here, we hydrothermally synthesized fluorescent SNPs by artificially generating optically active defect centers using tetraethyl orthosilicate and (3-aminopropyl)trimethoxysilane. The synthesized SNPs demonstrated strong blue photoluminescence originating from the dioxasilyrane (=Si(O2)) and silylene (=Si:) defect centers with the aid of aminopropyl groups. Furthermore, phosphorescence was observed at 459 nm, indicating the presence of silylene in SNPs. Finally, these SNPs have been successfully utilized as a fluorescent probe for bioimaging of normal, cancer, and macrophage cells.
关键词： silica nanoparticle,silylene,dioxasilyrane,phosphorescence,defect,photoluminescence,bioimaging
更新于2025-09-10 09:29:36