Papers by Author: Mehdi Ebadi

Abstract: One of the great challenges facing the society today is replacing fossil fuels by renewable energy sources. Hydrogen from non-carbon sources is considered one of the viable potentials to help alleviate reliance upon fossil fuels for energy and addressing the environmental problems. Photoelectrochemical water splitting was brought to attention since the pioneering work in 1972. Since then, numerous metal oxide photocatalysts have been investigated to enhance the overall water splitting performance. Up to now, Bismuth vanadate, BiVO₄ has emerged as the most promising photocatalyst in the construction of photoelectrochemical cell utilizing sunlight and water, the most abundant resources on earth. In this review, the principles, critical factors influencing the efficient BiVO₄-based photoanode properties such as the crystal and electronic properties are discussed. Subsequently, the methods synthesis and research efforts adopted to develop efficient and active BiVO₄ photoanode are presented.

Abstract: Crystalline thin of zinc selenide have been electrochemically deposited on conducting substrates of indium tin oxide, ITO glass. Initial investigation with voltammetry was done and shows that the zinc selenide films were stable towards oxidation. The best deposition potential obtained was at -0.95 V vs. Ag /AgCl while at lower deposition potentials, the films do not form well. Energy Dispersive Analysis and X-Ray spectrum indicate that the films deposited at 65oC and -0.95 V vs. Ag/AgCl have nearly stoichiometric Zn: Se ratio.

Abstract: Electrodeposition of ZnTe thin films by controlled potential method from aqueous solutions on ITO were done to investigate characteristics suitable as a window material in solar cells technology. The influence deposition of potential towards the Zn:Te ratio and the crystallinity are discussed. The electrodeposited films were investigated by using X-Ray Diffraction and Energy Dispersive Analysis of X-Ray. The Te content decreases at higher deposition potentials.

Abstract: The influence of a static magnetic field of 4.4 T on the electrodeposition process on copper plates immersed in a solution of Nickel and Cobalt ions is presented. The electrodeposited layers characterized by Scanning Electron Microscopy (SEM) including Energy Dispersive X-Ray (EDX), X-Ray Diffraction (XRD) and Atomic Force Microscopy (AFM).It was observed that the difference between the mass of electrodeposition with the application of a Permanent Parallel Magnetic Field to the electrode surface (PPMF) and the electrodeposited layers without the PPMF, increased with the increase of current density. The presence of the PPMF gave smoother electrodeposited surface compared to without the PPMF. The increase in current density gave fewer the cracks on the electrodeposited surface.

Abstract: This paper focuses on the electrodeposition of nickel from a Ni Watts solution in the presence and absence of a permanent parallel magnetic field (PPMF) to the cathode surface. It was found that the difference between the mass deposition were enhanced in the presence of PPMF and absence of a PPMF (B = 4.4 T) with increase of current density ( m= 0.413 to 4.173 mg cm2 in 6 min). The thickness of deposited layers with PPMF was smaller than without PPMF, therefore higher density of electrodeposited layers can be brought upon by the application of PPMF. The corrosion behavior of samples was tested in the presence and absence of a PPMF (9T). The Polarization resistance was reduced in the presence of the PPMF. The deposited layers were characterized by Scanning Electron Microscopy (SEM), X-ray Diffraction (XRD) and Atomic force Microscopy (AFM).