Silica nanoparticles have been functionalized by click chemistry and atom transfer radical polymerization (ATRP) simultaneously. First, the silanized silica nanoparticles were modified with bromine end group, and then the azide group was grafted onto the surface via covalent coupling. 3-Bromopropyl propiolate was synthesized, and then the synthesized materials were used to react with azide-modi...

Raman microspectroscopy is a powerful analytical technique in cultural heritage. However, results are often compromised by luminescence interference and poor sensitivity. Surface-enhanced spectroscopy (SERS) an alternative that can enhance the signal quench luminescence, but interaction of analyte metal substrate produces altered spectra. Shell-isolated nanoparticle-enhanced (SHINERS) promising...

The development of new highly sensitive and selective methods for microarray-based analysis is a great challenge because, for many bioassays, the amount of genetic material available for analysis is extremely limited. Currently, imaging and detection of DNA microarrays are based primarily on the use of organic dyes. To overcome the problems of photobleaching and low signal intensities of organi...

Hybrid metallic nanoparticles encapsulated in oxide shells are currently intensely studied for plasmonic applications sensing, medicine, catalysis, and photovoltaics. Here, we introduce a method the synthesis of Au@Ag@SiO$_2$ cubes with uniform silica shell variable adjustable thickness nanometer range; demonstrate their excellent, highly reproducible, tunable optical response. Varying thicknes...

a condensation of various isatins with indole derivatives has been carried out in the presence of 1,3-dibromo-5,5-dimethylhydantoin (dbdmh) as catalyst at 50 °c in ethanol in order to form 3,3-bis(indolyl) oxindoles. the products were obtained within 20-90 min by 70-96% yields. the efficacy of the procedure has been confirmed by catalyzing the condensation reaction of pyrrole which was used as ...

iron oxide (fe2o3) is widely used as a catalyst, pigment and gas sensitive material.  in this article, α-fe2o3 nano-rods were first synthesized via a simple chemical method using iron(iii) nitrate 9- hydrate (fe(no3)3.9h2o) as precursor. xrd pattern showed that the iron oxide nanoparticles exhibited alpha-fe2o3 (hematite) structure in nanocrystals. the single-phase α- fe2o3 nano-rods were prepa...

One-dimensional nanostructures such as nanowires, nanobelts, and nanotubes have attracted much attention as a result of their unique properties, which can be applied in the fabrication of biomedical sensors, optoelectronic devices, field-effect transistors, and field-emission devices, for example. In particular, one-dimensional nanostructures of metal oxides such as ZnO, SnO2, [3] a-Fe2O3, [4] ...

Polymer nanocomposites containing titanium oxide nanoparticles (TiO2 NPs) combined with other inorganic components (Si-O-Si or/and γ-Fe2O3) were prepared by the dispersion of premade NPs (nanocrystalline TiO2, TiO2/SiO2, TiO2/Fe2O3, TiO2/SiO2/Fe2O3) within a photopolymerizable urethane dimethacrylate (polytetrahydrofuran-urethane dimethacrylate, PTHF-UDMA). The physicochemical characterization ...

Tin–oxide nanoparticles with controlled narrow size distributions are synthesized while physically encapsulated inside silica mesoporous templates. By means of ultraviolet-visible spectroscopy, a redshift of the optical absorbance edge is observed. Photoluminescence measurements corroborate the existence of an optical transition at 3.2 eV. The associated band of states in the semiconductor gap ...

A unique hexagonal sheet-shaped NiO/CoO/Fe2O3 composite with irregularly shaped nanoparticles was fabricated for the first time through a simple co-precipitation and hydrothermal method. The NiO/CoO/Fe2O3 composite was characterized by numerous techniques (TEM, HRTEM, PXRD, EDX, ICP-AES, BET, and XPS) to confirm its structure and composition. This structure of the NiO/CoO/Fe2O3 composite may en...