A DFT study on the hydrogen desorption from the lithium borohydride and aluminohydride upon the addition of nanostructured carbon catalyzing agent

• Published in: International journal of hydrogen energy Vol. 42; no. 5; pp. 3019 - 3026
• Main Authors: Paduani, C., Rappe, Andrew M.
• Format: Journal Article
• Language: English
• Published: United Kingdom Elsevier Ltd 02.02.2017; Elsevier
• Subjects: Catalyst; Dehydrogenation; DFT; Light metal hydrides; DFT; Light metal hydrides; Dehydrogenation; Catalyst
• ISSN: 0360-3199; 1879-3487
• DOI: 10.1016/j.ijhydene.2016.09.124

Here we study in van der Waals-corrected DFT calculations the dehydrogenation mechanism of the light metal hydrides LiBH4 and LiAlH4 by focusing on the effect of the addition of the carbon fullerene C60 as catalyzing agent. The results show a rather significant gain in the energy cost for H desorption in the presence of the catalyst, which is substantially even more pronounced when considering boron-doping the fullerene. In the source of this effect is the disturb introduced in the distribution of bonding charge upon the hybridization of states in the interplay cluster-fullerene with a consequent weakening of the hydrogen bonds, leading therein to an enhanced kinetics for the hydrogen release. [Display omitted] •The energy cost for hydrogen desorption from LiAlH4 is lower than in LiBH4.•The buckminsterfullerene C60 acts as catalyst imposing a significant gain in energy for H removal.•A further decrease in the energy cost for H desorption takes place upon B-doping the fullerene.