Effect of milling and doping on decomposition of NH3BH3 complex

In this work we considered three different samples: borane ammonia (BA) complex as received, ball milled BA and, finally, BA subjected to ball milling and doped with 1 mol% of hydrogen hexachloroplatinate hydrate. Their crystalline structure was described by XRD and morphology was investigated using SEM and EDS techniques. In order to describe samples behaviour in hydrogen release we plotted TGA curves and thermal decomposition tests were realized. We verified that ball milling increases the BA cristallinity and changes its morphology enhancing the amount of evolved gas. Both the milled and the doped samples show an increase of the pre-exponential factor in the Arrhenius equation. The activation energy remains almost unchanged for the doped sample and it increases for the milled one. As result it was found that the decomposition of 1 mol% doped sample could be provided by waste heat coming from a PEM fuel cell.