Hydrogen Storage still remains the technology bottleneck for a more widespread use of hydrogen. Solid complex hydrides such as amides, alanates and borohydrides have been investigated showing reversibility while keeping in general higher density than metallic hydrides. One of the main problems with these materials is the complex crystal structures of the hydrides collapses into elemental components of the initial materials. Large pressures and often needed to recomnbine the reversible materials.NaAlH4 dehydrogenates following the reaction:NaAlH4 ¿--- 1/3Na3AlH6 +2/3 Al+ H2 ¿-- NaH +Al +3/2H2The presence of a catalyst improves the activity of the reaction down to more manageable temperatures and this seems to be the prototipical system to study the catalytic effects.we will use isotope labelling to study this material.