Energetic Characteristics of Exfoliated Magnesium Boride Nanosheet

Boron combustion has garnered much attention due to its extremely high gravimetric and volumetric energy density. However, several inherent characteristics of boron prohibit fast response on heating and complete combustion. In this work, a boron-rich two-dimensional (2D) nanosheet is studied in order to overcome the limitations of boron ignition and combustion. Boron-rich MgB₂ nanosheet is prepared by exfoliation from bulk magnesium diboride (MgB₂) with Mg etching; then, its oxidation behaviors and energetic performances are analyzed by material characterizations in slow heating and fast heating conditions. This work reports that MgB₂ nanosheet is oxidized more favorably in slow heating conditions than bulk MgB₂. Even under fast heating conditions like Xenon (Xe) flash ignition, MgB₂ nanosheet has lower minimum flash ignition energy, higher combustion efficiency, and faster pressurization rate than bulk MgB₂, boron nanoparticle, and boron/magnesium mixture. This result shows MgB₂ nanosheet can be regarded as a promising 2D solid fuel with extraordinary energetic characteristics.