(458g) Boron-Based Analogs of Graphene Exfoliated from Layered Metal Diborides As Catalytic Additives to Improve the Performance of Energetic Materials

Several research groups are investigating the effect of nanoscale boron as a catalytic additive for improving the energetics of the system. Nanoscale boron grabs the attention of the scientific community because of the scope of enhanced accessibility of high energy density of elemental boron. The primary challenge in utilizing the potential of elemental boron is the formation of an inert boron oxide layer. We can overcome this challenge by combining boron with energetic metals, and therefore metal borides are the best alternative as they inherently possess both boron and metal in their native chemical structure. However, the knowledge on utilizing the potential of metal borides is in its incipient stages. In this talk, we present that layered metal diborides (LMDBs) of the form MB₂ are excellent catalytic additives in improving the energetics of AP. Our group has developed the science of exfoliating LMDB crystals to obtain two-dimensional (2D) boron-based nanostructures.^1–3 These Boron-based nanostructures possess enhanced surface area with pronounced accessibility to the active sites. We demonstrate that the boron-based nanostructures or boron-based analogs of graphene obtained by exfoliation of LMDBs show superior catalytic activity in tuning the energetics of AP. Here, dry ball milling approach is used to exfoliate LMDBs to yield large-scale production of boron-based nanostructures. The physicochemical properties of these boron-based nanostructures were obtained through XRD, FE-SEM, TEM, AFM, FTIR, PSA (particle size analysis), and BET surface area. The catalytic activity of these boron-based nanostructures on thermal decomposition of AP was studied using DSC and TGA. We found that the catalytic activity of these nanostructures increases with an increase in milling time. Addition of a small fraction of these nanostructures to AP depicts a remarkable catalytic activity in the system. This study presents a new perspective to utilize the potential of boron-based nanostructures obtained from LMDBs as a super active nanocatalyst and adds an immense prospect to the field of energetic materials.

References

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