Sharif Digital Repository

The corrosion inhibition of glycine-based dithiocarbamates with benzyl (BDTC) and propyl (PDTC) groups were investigated for cold rolled carbon steel (CRS) in 0.5 M HCl, indicating that the compounds as mixed type inhibitors significantly reduced the corrosion rate of the CRS due to the formation of a stable protective film on the metal surface. As confirmed by ATR-FTIR, SEM, AFM, XPS and theoretical studies, chemically adsorbed BDTC molecule is a better corrosion inhibitor with higher corrosion efficiency of about 98% at room temperature and a better thermal stability attributed to the Fe-S and Fe-N bindings, and in addition, to the presence of the benzene ring in the molecular structure. ©... 

Nanostructured molybdenum oxide was potentiodynamically deposited onto a stainless steel surface from an aqueous bath by cycling the potential between 0 and -0.75 V vs. Ag/AgCl. The deposit consisted of particulates in the range of 30 to 80 nm. Electrochemical studies under galvanostatic charge/discharge and also impedance spectroscopy revealed capacitive behavior in the potential range of -0.3 to -0.55 V vs. Ag/AgCl with the value of 477 F g-1 at 0.1 mA/cm2. An equivalent circuit comprising of three parallel branches consisting of double-layer capacitance, Warburg impedance, and a constant phase element signifying pseudo-capacitance each coupled with their corresponding resistances was... 

RGO-α-Fe2O3/β-FeOOH ternary heterostructure composite has been developed as an active photocatalyst for photoelectrochemical water splitting. RGO-α-Fe2O3/β-FeOOH has been successfully synthesized through one-pot hydrothermal-ionic liquid assisted route using tetrabutyl ammonium L-methioninate [TBA][L-Met]and graphene oxide (GO). The electrochemical studies were carried out to demonstrate the oxygen evolution reaction (OER)and photocatalytic activities. The overpotential reduction by rGO-α-Fe2O3/β-FeOOH sample was higher than the nanobean α-Fe2O3/β-FeOOH and pristine α-Fe2O3 samples. The photocurrent density enhanced for rGO-α-Fe2O3/β–FeOOH urchin-like structure and obtained as 0.62 mA·cm−2.... 

Lithium ion batteries as one of the most important energy storage equipments, have several challenges including capacity drop as number of cycles increases. Cathode particle coating is an effective approach in improvement of electrochemical performance of the batteries. In this study, TiO2-Ag coating was used to improve NCM cathode performance. The microstructure and crystal structure properties of coated NCMs were evaluated by the FE-SEM and XRD. Electrochemical behavior of the batteries was investigated by cycling performance analysis and EIS. TiO2 coating was deposited as a uniform layer and Ag coating was precipitated as dispersed nanoparticles. The results shows that using of TiO2-Ag... 

The early stages of nucleation and growth of nanostructures can control the shape and final size of the fabricated nanostructure. Therefore, the study of the nucleation and growth mechanism of nanostructures is of great importance. The purpose of this study is to investigate the nucleation and growth mechanism of nickel nanocones from a chloride-based bath containing ethylene ammonium dichloride as a crystal modifier. Cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and chronoamperometry tests were employed to investigate the nucleation and growth mechanism and also the mechanism of crystal modifier performance on the growth of nanocones. Electrochemical studies revealed... 

A novel modified electrode is reported for the electrochemical investigation of the oxidation mechanism and also voltammetric determination of raloxifene (RLX). The surface of the electrode was modified with a thin layer of reduced graphene oxide-carbon nanotube nano-composite (rGO-CNT) was prepared, and successfully employed for the electrochemical studies of RLX. The morphology of the sensor surface was characterized by using a scanning electron microscopy. RLX Oxidation response significantly increased at the GCE covered with rGO-CNT, regarding the bare and CNT or rGO functionalized GCE. Experimental parameters affecting the RLX response were optimized and mechanism of the RLX oxidation... 

The development of active, durable, cost-effective, and stable electrocatalysts is an urgent need for various industrial fields including renewable energy systems. The state-of-the-art catalysts suffer from poor water splitting activity in alkaline media due to their sluggish kinetics, high cost, and scarcity on earth to be scaled up. Herein, we present an electrochemical analysis of a nanostructured electrocatalyst based on a face-centered cubic (FCC) copper-rich Cu-Ni-Fe-Cr-Co alloy with a quasi-spherical morphology electrodeposited on a highly porous nickel substrate. Electrochemical studies determine the enhanced electrocatalytic activity toward both hydrogen and oxygen reactions in an... 

A stable copper (hydr)oxide-modified electrode was prepared in 0.5 mol/L NaOH solution by cyclic voltammetry in the range of -250 to 1000 mV. It can be used for electrochemical studies in the range of -250 to 1000 mV without interfering peaks because there is no oxidation of copper. During an anodic potential sweep, the electro-oxidation of saccharose on Cu occurred by the formation of CuIII and this reaction also occurred in the early stages of the reversed cycle until it is stopped by the negative potentials. A mechanism based on the electro-chemical generation of CuIII active sites and their subsequent consumption by saccharose was proposed, and the rate law and kinetic parameters were... 

Energy and environment crises motivated scientists to develop sustainable, renewable, and clean energy resources mainly based on solar hydrogen. For this purpose, one main challenge is the low cost flexible substrates for designing earth abundant efficient cocatalysts to reduce required water oxidation overpotential. Here, a systematic morphological and electrochemical study has been reported for cobalt oxide/hydroxide nanoflakes simply electrodeposited on four different commercially available substrates, titanium, copper sheet, steel mesh, and nickel foam. Remarkable dependence between the used substrate, morphology, and electrocatalytic properties of nanoflakes introduced flexible porous... 

The preparation and characterization of new heteronuclear-platinum(ii) complexes containing a 1,1'-bis(diphenylphosphino)ferrocene (dppf) ligand are described. The reaction of the known starting complex [PtMe(κ2N,C-bipyO-H)(SMe2)], A, in which bipyO-H is a cyclometalated rollover 2,2'-bipyridine N-oxide, with the dppf ligand in a 2:1 ratio or an equimolar ratio led to the formation of the corresponding binuclear complex [Pt2Me2(κ2N,C-bipyO-H)2(μ-dppf)], 1, or the mononuclear complex [PtMe(κ1C-bipyO-H)(dppf)], 2, respectively. According to the reaction conditions, the dppf ligand in 1 and 2 behaves as either a bridging or chelating ligand. All complexes were characterized by NMR spectroscopy.... 

Thin carbon nanoparticle/Nafion film (CNP/N), as a novel electrode material, is formed on the surface of the glassy carbon electrode in a simple solvent evaporation process. The electrochemical behavior of Azathioprine (Aza) at the CNP/N-modified electrode is investigated in detail by the means of cyclic voltammetry. During the electrochemical reduction of Aza, an irreversible cathodic peak is appeared. Cyclic voltammetric studies indicated that the reduction process has an irreversible and adsorption-like behavior. The observed reduction peak is attributed to a four-electron process referring to the reduction of nitro group to the corresponding hydroxylamine. The prepared electrode showed... 

Two electrochemical sensors based on modified glassy carbon electrodes with carbon nanostructures as graphene (GCE–EG) and carbon nanotubes (GCE–CNT) were evaluated for morpholine analysis. The carbon nanostructures were obtained and characterized using X-ray photoelectron spectroscopy, Raman spectroscopy, X-ray diffraction, transmission electron microscopy, high-resolution transmission electron microscopy and cyclic voltammetry. All spectroscopic and microscopic techniques confirmed the procurement of graphene and CNT. The electrochemical studies proved the efficient behaviour of both electrodes GCE–EG and GCE–CNT in sensing and detection of morpholine via differential pulse voltammetry....