Sharif Digital Repository

Hydrogen sulfide, H2S, is a toxic gas and has detrimental effects on human health and the oil and gas industry. Therefore, its identification is very important. According to the devastating effects of this gas, then, the general mechanisms have been studied for gas detection. In addition, by highlighting the benefits of the multilayer nanostructure electrochemical sensors, an applicable and efficient method for the industrial production of these sensors has been investigated. In this regard, the sol-gel method is used to prepare the SnO2-CuO multilayer thin film and the advantages of this method was compared to PVD method. Also sensor properties of both deposition methods have been... 

Recently, Supercapacitors, as one of the most important energy storage devices, have attracted attensions by the scientists. Supercapcitor devices with appoporate design can store energy by two different mechanisms: i) physical (like conventional capacitors, i.e. by using polarization of the electrolyte, and ii) formation of electric double layer) and chemical mechanisms (like batteries, with reversible faradic reactions). These energy storage mechanisms allow these devices not only store high energy density but also they can provide high power density. In this project, two Co3O4/Co(OH)2 and Co3O4@Sponge-like rGO electrodes are made with chemical and electrochemical methods. To characterize... 

In this study, an alkaline bath for co-deposition of Fe and Pd was selected. In order to investigate the mechanism of deposition, each of the metals iron and palladium electrodeposited from selected bath separately; and the kinetics of electrodeposition by electrochemical techniques such as linear voltammetry, cyclic voltammetry, chronoamperometry and chronopotentiometry were evaluated. Electrodeposition processes of Fe, Pd and their alloy were irreversible and under diffusion of reducing agents are controlled. Moreover the electroreduction of palladium from utilized bath was performed in two steps. At following, the mechanism of iron– palladium alloy electrocrystallization was discussed and... 

Herein, cupric oxide (CuO)/graphitic carbon nitride (g-C3N4) is synthesized under microwave irradiation for enhanced photoelectrochemical (PEC) performance and photostability. A facile, one-pot method was utilized to directly deposit the nanocomposite onto FTO from a solution containing copper precursor and urea. Possible mechanisms of CuO/g-C3N4 formation and PEC performance improvement were examined via XRD, FTIR, FESEM, XPS, UV-Vis, and PL. Controlled amounts of urea determined the morphological evolution of CuO and the formation of a protective carbon layer, while its excess quantity converted to g-C3N4 in the presence of CuO. Through heat treatment of the nanocomposite, carbon-doped...