in this work, electrocatalyst with core-shell structure (pd as core and pt as shell on vulcanxc-72r) was synthesis. not only this structure can reduce the amount of platinum but it also can increase the gas diffusion electrode (gde) performance in cathode reaction (oxygen reduction reaction or orr) of polymer electrolyte membrane fuel cell (pemfc). to this meaning, one series of electrocatalyst...

Objective(s): This paper describes coating of magnetite nanoparticles (MNPs) with amorphous silica shells.   Materials and Methods: First, magnetite (Fe3O4) NPs were synthesized by co-precipitation method and then treated with stabilizer molecule of trisodium citrate to enhance their dispersibility. Afterwards, coating with silica was carried out via a sol-gel approach in which the electrostati...

the photocatalytic coatings were prepared via incorporating the modified titania nanoparticles into epoxy-based inorganic-organic hybrid coatings. titania nanoparticles were first synthesized from tetra-n-butyl titanate using sol-gel methods by two different calcination treatments, i.e., in mild condition (80°c) and 500°c. the formed anatase nanoparticles were further modified as titania-silica...

In order to implement an integrated optical quantum circuit, designing waveguides based on the quantum box is of prime importance. To do this we have investigated optical waveguide both with and without optical pumping. The rate of absorption and emission using an array of AlGaAs/GaAs quantum box core/shell structure in the optical waveguide with various pumping intensities has computed. By con...

The nanocomposite consists of the Ag as a core and Pt as shell on the surface of graphene nanosheets (Ag/Pt-G) was synthesized with a simple method and used as a novel electrochemical platform for an efficient catalyst for oxidation of the ethanol, methanol and formic acid. The morphology and electrochemical properties of Ag/Pt-G nanocomposite were investigated by TEM, X-ray diffraction, and vo...

In this thesis, I present a theoretical model for the Si core/SiGe shell core-shell nanowire system. A model for the single carrier pocket core-shell nanowire is first developed, along with the boundary conditions of a circular wire and sharp interfaces between the two media. A numerical scheme is then developed for the core-shell nanowire system, along with educated approximations for the nume...

In order to implement an integrated optical quantum circuit, designing waveguides based on the quantum box is of prime importance. To do this we have investigated optical waveguide both with and without optical pumping. The rate of absorption and emission using an array of AlGaAs/GaAs quantum box core/shell structure in the optical waveguide with various pumping intensities has computed. By con...

The photocatalytic coatings were prepared via incorporating the modified titania nanoparticles into epoxy-based inorganic-organic hybrid coatings. Titania nanoparticles were first synthesized from tetra-n-butyl titanate using sol-gel methods by two different calcination treatments, i.e., in mild condition (80°C) and 500°C. The formed anatase nanoparticles were further modified as Titania-Silica...