Boron-based hydrides for chemical hydrogen storage

Abstract

SUMMARY The development of the hydrogen economy is hampered by many issues connected with production, storage, distribution, and end‐use. Although the hydrogen storage problem is particularly difficult, there are several attractive solutions under investigation, and chemical hydrogen storage (involving hydrogen‐rich materials) has shown much promising properties. The boron‐based materials are typical examples. They have high hydrogen densities, with up to four reactive B − H bonds. Most of the works have focused on dehydrogenation by hydrolysis or thermolysis so that it takes place in high extent in mild conditions. The first materials studied have been lithium borohydride, sodium borohydride, and ammonia borane. However, their development has been hindered by technical issues such as very high dehydrogenation temperatures, incomplete reaction, and purity of the produced hydrogen. To get round such problems, new materials have been proposed since the mid‐2000s. Interestingly, those materials present attractive attributes, but also drawbacks. This is illustrated in the present review. We believe that boron‐based hydrides have a significant potential in chemical hydrogen storage, but their implementation depends on the recyclability of the solid by‐products; this seems to be the key factor. Copyright © 2013 John Wiley & Sons, Ltd.

Hydrazine Borane and Hydrazinidoboranes as Chemical Hydrogen Storage Materials

“…Moury et al [24] envisaged stabilization of the aqueous solution by increasing the pH to 8 with the help of sodium hydroxide NaOH. Similar action has been efficient for hindering the spontaneous hydrolysis of sodium borohydride [9]. After one month, improved stability was noticed: 97% of hydrazine borane remained unchanged.…”

“…The theoretical gravimetric hydrogen storage capacity will thus be impacted (Figure 3): 7.3 wt% for N2H4BH3-2H2O in Equation (7); 6 wt% for N2H4BH3-3H2O in Equation (8); and 5.1 wt% for N2H4BH3-4H2O in Equation (9).…”

“…With respect to chemical hydrogen storage materials, atomic hydrogen is chemically bonded to a heteroatom and molecular hydrogen is released by solvolysis or thermolysis [4][5][6]. Borohydrides [8] and nitrogen-containing boranes (also called B-N-H compounds or boron-and nitrogen-based materials) [9] are typical examples.…”

An assessment of the viability of hydrogen generation from the reaction of silicon powder and sodium hydroxide solution for portable applications

“…This is a particular issue for portable applications, where a high gravimetric hydrogen storage efficiency is required [7]. Thus, methods of splitting water into hydrogen and oxygen using chemicals with a higher density than hydrogen have become increasingly studied [8][9][10][11][12]. Silicon is considered to be an especially promising material for this type of application because of its high theoretical gravimetric hydrogen storage efficiency of 14 wt.% (although it should be noted that the hydrogen is obtained from the water with which the silicon reacts, rather than being stored in the silicon itself), low cost and abundance.…”

Hydrogen generation from nanoflower platinum films

“…Chemical hydrides hold great promise in this respect due to their capacity to store hydrogen as a solid [1]. Among the chemical hydrides, boron hydrides have the largest volumetric and mass hydrogen densities [2]. The two major methods to produce hydrogen from a chemical hydride are hydrolysis and thermolysis.…”