Sharif Digital Repository

Core-Shell structures of Ag@Pt Nanoparticles (NPs) dispersed on different carbon base supports such as Graphene Oxide (GO), Multiwall Carbon Nanotubes (MWCNT) and Carbon black (CB) Vulcan applied to the oxygen reduction reaction (ORR) in a Proton Exchange Membrane Fuel Cell (PEMFC). Electrocatalysts synthesized through the ultrasonic treatment method. The morphology of as prepared materials characterized through the High Resolution Transmission Electron Microscopy (HRTEM) and X-ray diffraction (XRD) analyses. The ORR activities and stabilities of electrocatalysts studied through electrochemical measurements of Cyclic Voltammetry (CV) and single cell tests, respectively. Results revealed all... 

In Li-ion batteries the interface between the nano-size spherical core graphite and its surrounding solid electrolyte interphase (SEI) layer, just inside SEI is susceptible to damage. Thus, accurate determination of the associated elastic fields is one of the challenges in optimizing the lifetime and capacity of Li-ion batteries. The required precision is achieved by considering the core graphite which belongs to the crystal class D6h as homogeneous spherically isotropic and SEI layer as functionally graded (FG) isotropic material. Moreover, to account for the surface/interface effects appropriately the core-shell nano-structure subjected to the diffusion-induced time-dependent nonuniform... 

Here, cobalt oxide nanostructures synthesized on vertically aligned copper oxide nanowires (NWs) have been investigated as a possible anode material for Lithium-ion batteries (LIBs). Copper oxide NWs were formed by thermal oxidation of electrochemically deposited copper on the stainless steel mesh substrate. The process used allows the formation of highly dense copper oxide NWs with excellent adhesion to the conductive current collector substrate. A simple hydrothermal method was implemented for the deposition of cobalt oxide nanostructures on the copper oxide NWs. The as-prepared binder-free copper oxide@cobalt oxide NWs electrode exhibits a high initial specific capacity of 460 mAh g-1 at... 

Biogenic amines (BAs) are known as substantial indicators of the quality and safety of food. Developing rapid and visual detection methods capable of simultaneously monitoring BAs is highly desired due to their harmful effects on human health. In the present study, we have designed a multicolor sensor array consisting of two types of gold nanostructures (i.e., gold nanorods (AuNRs) and gold nanospheres (AuNSs)) for the discrimination and determination of critical BAs (i.e., spermine (SM), tryptamine (TT), ethylenediamine (EA), tyramine (TR), spermidine (SD), and histamine (HT)). The design principle of the probe was based on the metallization of silver ions on the surface of AuNRs and AuNSs...