Metal borides have attracted the attention of researchers due to their useful physical properties and unique ability to form high hydrogen-capacity metal borohydrides. We demonstrate improved hydrogen storage properties of a nanoscale Mg–B material made by surfactant ball milling MgB2 in a mixture of heptane, oleic acid, and oleylamine. Transmission electron microscopy data show that Mg–B nanoplatelets are produced with sizes ranging from 5 to 50 nm, which agglomerate upon ethanol washing to produce an agglomerated nanoscale Mg–B material of micron-sized particles with some surfactant still remaining. X-ray diffraction measurements reveal a two-component material where 32% of the solid is a strained crystalline solid maintaining the hexagonal structure with the remainder being amorphous. Fourier transform infrared shows that the oleate binds in a “bridge-bonding” fashion preferentially to magnesium rather than boron, which is confirmed by density functional theory calculations. The Mg–B nanoscale material is deficient in boron relative to bulk MgB2 with a Mg–B ratio of ∼1:0.75. The nanoscale MgB0.75 material has a disrupted B–B ring network as indicated by X-ray absorption measurements. Hydrogenation experiments at 700 bar and 280 °C show that it partially hydrogenates at temperatures 100 °C below the threshold for bulk MgB2 hydrogenation. In addition, upon heating to 200 °C, the H–H bond-breaking ability increases ∼10-fold according to hydrogen–deuterium exchange experiments due to desorption of oleate at the surface. This behavior would make the nanoscale Mg–B material useful as an additive where rapid H–H bond breaking is needed.

Laboratory chemical synthesis research typically lacks the preplanned hazard responses found in production-scale industrial laboratories. Chemical safety management is a known challenge in education-based facilities, which is concerning for academic and national laboratory environments working with inexperienced student researchers. At the Molecular Foundry, a U.S. Department of Energy (DOE) user facility, a chemical safety management form has been developed that follows DOE’s Integrated Safety Management (ISM) process, which evaluates the risks and hazards associated with all forms of work. An ISM form for chemical synthesis is described here in detail. It is regularly used to guide chemical safety discussions between researchers and supervisors, to plan accident responses, and to establish triggers, at which point a reevaluation of the work is needed. The form makes it straightforward to know what limits researchers may work within and makes it clear which procedure changes will require a new safety assessment and discussion before work continues. The ISM form for synthesis is being successfully used in three fields of chemistry: Inorganic, Organic, and Biological. The form has also been adapted for liquid sample preparation in electron microscopy. Upper management, supervisors, students, and general users are engaged in this process. It is hoped that sharing this knowledge will enable educational institutions and other laboratories to develop similar methods to help researchers and supervisors understand the hazards as well as the working limits of any protocol, helping researchers to work more independently and safely within the laboratory.

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Hydrogen (H 2 ) shows great promise as zero-carbon emission fuel, but there are several challenges to overcome in regards to storage and transportation to make it a more universal energy solution. Gaseous hydrogen requires high pressures and large volume tanks while storage of liquid hydrogen requires cryogenic temperatures; neither option is ideal due to cost and the hazards involved. Storage in the solid state presents an attractive alternative, and can meet the U.S. Department of Energy (DOE) constraints to find materials containing > 7 % H 2 (gravimetric weight) with a maximum H 2 release under 125 °C. While there are many candidate hydrogen storage materials, the vast majority are metal hydrides. Of the hydrides, this review focuses solely on sodium borohydride (NaBH 4 ), which is often not covered in other hydride reviews. However, as it contains 10.6% (by weight) H 2 that can release at 133 ± 3 JK −1 mol −1 , this inexpensive material has received renewed attention.