Abbas Ranjbar

Hydrogen Storage Properties of Mg-BCC Composite

MgH2 with 10 wt% Ti0.4Mn0.22Cr0.1V0.28 (termed BCC for its body-centered cubic structure) nanocomposite was fabricated by ball milling using different ball-to-powder weight ratios. The X-ray diffraction patterns make it clear that pure Mg powder is partly transformed to MgH2, while by adding the BCC, its hydriding becomes complete. The scanning electron microscope images showed that the BCC particles were uniformly dispersed on the surface of the Mg particles. Differential scanning calorimetry traces of the samples showed that the addition of the BCC obviously decreases the desorption temperature, and an additional decrease is observed from increasing the ball-to-powder weight ratio. The hydriding/dehydriding and the pressure-composition isotherm curves indicate significant improvement in the absorption/desorption kinetics and the hydrogen storage capacity of MgH2 from both adding the BCC and increasing the ball-to-powder weight ratio. The results indicate that the BCC acts as a medium that facilitates hydrogen absorption during hydrogenation on Mg, thus improving hydrogen storage capacity and absorption/desorption kinetics.

Application of Conducting Polymers in Solar Water-Splitting Catalysis

Water splitting is the general term for a chemical reaction in which water is separated into its constituent materials, oxygen and hydrogen. Hydrogen is widely considered to be an ideal fuel of the future due to its potential to replace fossil fuels. The key to an energy-efficient water-splitting process lies in catalysts that can carry out the water oxidation and reduction reactions with minimal energy losses. Conducting polymers are attractive materials for this technology and application because they may combine several desirable properties, including electronic conduction, ionic conduction, sensor functionality, and electrochromism. In this chapter, water splitting assisted by or driven by illumination with sunlight and involving conducting polymers is reviewed. The properties of conducting polymers that make them favorable for this purpose are also discussed. Comparisons of these properties with those of conventional water-splitting materials are made. Finally, a statement of research and achievements of solar hydrogen production through water splitting using conductive polymers will be reported.