Boron-Nitride fullerene as a potential solid-state hydrogen storage medium
16 May 2016
Researchers in India report that experimentally synthesized B24N24 (boron-nitride) fullerene can serve as a potential reversible chemical hydrogen storage material with hydrogen storage capacity of up to 5.13 wt %. A paper on their work is published in the journal ChemSusChem.
Fullerenes are large hollow spheroidal cages of carbon atoms; a regular boron-nitride fullerene substitutes nitrogen for carbon in equal numbers—e.g., B24N24.
Designing an ideal hydrogen-storage material depends on attaining a fine balance of optimal thermodynamics and kinetics for hydrogenation/dehydrogenation of the material under ambient conditions along with a healthy storage capacity. Additionally, all the chemical/physical transformations involved, must be sustainable in the long run. When we take into account all of these issues, the number of promising materials are very limited and finding a better alternative is imperative.
The high curvature of BN fullerenes makes hydrogenation favorable compared to that for BNNTs [BN nanotubes]. … Here, we first systematically investigated the overall hydrogenation thermodynamics of a series of near-ideal BN nanomaterials (e.g., BNNT, B12N12,B16N16,B24N24, and B36N36).
—Ganguly et al.
The theoretical studies showed that hydrogenation and dehydrogenation of the fullerene framework can be achieved at reasonable rates using existing metal-free hydrogenating agents and base metal-containing dehydrogenation catalysts.
Resources
Ganguly, G., Malakar, T. and Paul, A. (2016), “In Pursuit of Sustainable Hydrogen Storage with Boron-Nitride Fullerene as the Storage Medium,” ChemSusChem doi: 10.1002/cssc.201600213
A step in the right direction?
Good but may not be good enough to significantly reduce the size of the on-board H2 tanks.
Posted by: HarveyD | 16 May 2016 at 08:28 AM
This is not about the size, but the *weight* of a potential tank - I would expect that the volumetric energy density is fairly low of these systems. B and N are lightweight and the BxNy structure contains a lot of open and unused volume.
In addition, this works only at liquid N2 temperature, which means you need a cryotank for the material...
Posted by: Battman | 27 May 2016 at 03:17 AM
@Battman: "...this works only at liquid N2 temperature..."
--> No. From the paper it looks like, they tested it at room temperature. And in their abstract they cite something from the DoE, stating that the goal is at least the range of -40 to +85 °C...
It also seems, that 5.5 wt % would be a "reasonable target" - again a statement from their abstract, citing the DoE...
Posted by: Bernhard | 29 May 2016 at 11:58 PM