Catalytic Application of Carbon-based Nanostructured Materials on Hydrogen Sorption Behavior of Light Metal Hydrides

Abstract

The development of hydrogen storage materials with favorable thermodynamics (e.g., kinetics, desorption/adsorption temperature) has attracted considerable attention in recent years. Alanates, amide-hydride mixtures and magnesium hydride are the candidates with the most potential storage material due to their high hydrogen storage capacity and good reversibility, but each has its own limitations (e.g., high desorption temperature and sluggish kinetics). Carbon has many allotropes such as graphite, activated carbon, fullerenes, carbon nanotubes, and the most recent, graphene, etc. These have novel properties which are useful in many new innovative applications. Several recent investigations have also demonstrated the benefi cial effect of carbon materials as catalyst for enhancing sorption behavior of different light hydrogen storage materials. Carbon with a small curvature radius exhibits prominent "catalytic" effect for light metal and complex hydrides. The reduction in curvature radius of carbon nanostructures enhances the electron affi nity and interaction of carbon with hydrogen because the hydrogen release/combination energy has been changed, and consequently, the de-/rehydrogenation kinetics of the material is improved. In this chapter, we will highlight the current advances (including our recent works) in the hydrogen sorption enhancement of metal and complex hydrides by incorporating carbon nanomaterials as a catalyst. There will be a particular emphasis on carbon nanotubes, carbon nanofi bers and graphene employed as a catalyst for the aforesaid hydrogen storage materials. © 2014 Scrivener Publishing LLC. All rights reserved.