Glenn Hefter

The idea of an economy supported by hydrogen is still being considered by government bodies and major oil companies. The extensive use of hydrogen as a fuel has many applications in pollution-free technologies which could be of every-day use in society. Examples are in transportation and power generation; other uses include chemical technology, metallurgy, effluent processing and water production. For mass application the most appropriate process for hydrogen production is water electrolysis. To this end, a simplified description of the hydrogen and oxygen evolution mechanisms is presented. Understanding these mechanisms will provide a basis for making water electrolysis more efficient. For this reason special attention is given to the design of catalysts for water electrolysis.

Broadband dielectric relaxation spectroscopy (DRS) is a powerful tool for studying the nature and dynamics of room-temperature ionic liquids, as well as providing the only means to directly measure their dielectric constants. The DR spectra of neat ionic liquids exhibit many modes, especially at high frequencies, where they reflect 'intermolecular' vibrations and librations. Detailed investigations have also been made into mixtures of ionic liquids with molecular solvents of varying character. The spectra indicate that typical ionic liquids retain their chemical nature even after significant dilution by a molecular solvent such as dichloromethane. Contrary to popular belief, there is little evidence for the existence of discrete ion pairs in the neat ionic liquids; such species appear to exist only at high dilution (typically at xIL < 0.1) in molecular solvents.

(Book Overview) This new book discusses important topics on one of the most basic of thermodynamic properties, namely Solubility - a property which underlies most industrial processes. The objective of the book is to bring together new, exciting and disparate topics, all related to Solubility, in a single volume, so that readers can extend their horizons and relate hitherto unrelated topics, leading to innovative and creative ideas.

Fourier transform infrared (FTIR) spectroscopy has been used to study the nature of hydrogen, oxygen and nitrogen bonds In a-Si thin films. The samples were prepared by rf sputtering under different deposition conditions to produce hydrogen contents ranging from 15 to 35 at.%. Slightly contaminated samples were found to contain nitrogen and oxygen ranging from 0.0 - 1.5 and 0.0 - 3.0 at.% respectively. Annealing vas performed by heating the samples in a hydrogen atmosphere, usually for 30 minutes, at temperatures ranging from 150 to 550 C. The FTIR spectra, taken for the as-deposited sample and after each annealing step, have been deconvoluted into their component peaks using the simplex algorithm. Our results demonstrate that for a particular type of silicon-hydrogen group, evolution of hydrogen takes place at a lower temperature from the surface and/or the near surface region than from the bulk, On the other hand, oxygen and nitrogen related bonds in the a-Si network change configurations on annealing.