Lithium zirconate powder reacts immediately with ambient CO2 in the range of 450 to 550°C. Moreover, the products react and return reversibly to lithium zirconate at temperatures above 650°C. Utilizing this reaction, the possibility of a CO2 separation system which operates at around 550°C is suggested. A CO2 separation process operable at temperatures beyond 500°C may have a special benefit, because the separation can be achieved directly during the fuel reforming process, where high CO2 concentration is expected.

Carbon nanotubes have been proposed as promising hydrogen storage materials for the automotive industry. By theoretical analyses and total-energy density functional theory calculations, we show that contribution from physisorption in nanotubes, though significant at liquid nitrogen temperature, should be negligible at room temperature; contribution from chemisorption has a theoretical upper limit of 7.7 wt %, but could be difficult to utilize in practice due to slow kinetics. The metallicity of carbon nanotube is lost at full hydrogen coverage, and we find strong covalent C-H bonding that would slow down the H 2 recombination kinetics during desorption. When compared to other pure carbon nanostructures, we find no rational reason yet why carbon nanotubes should be superior in either binding energies or adsorption/desorption kinetics.

Large-scale perpendicularly aligned helical carbon nanotube arrays were prepared by co-pyrolysis of Fe(CO)5 and pyridine onto the pristine quartz glass plates in a tube furnace at 900-1100 degrees C under a mixture flow of Ar and H2. The resultant aligned helical carbon nanotubes could not only facilitate the structure-property characterization for helical carbon nanotubes but also allow them to be effectively incorporated into devices for practical applications.

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