Bagge-Hansen M, Bastea S, Hammons J A, Nielsen M H, Lauderbach L M, Hodgin R L, Pagoria P, May C, Aloni S, Jones A, Shaw W L, Bukovsky E V, Sinclair N, Gustavsen R L, Watkins E B, Jensen B J, Dattelbaum D M, Firestone M A, Huber R C, Ringstrand B S, Lee J R I, van Buuren T, Fried L E, Willey T M
Lawrence Livermore National Laboratory, 7000 East Ave., Livermore, CA, 94550, USA.
The Molecular Foundry, Lawrence Berkeley National Laboratory, 67 Cyclotron Rd., Berkeley, CA, 94720, USA.
Nat Commun. 2019 Aug 23;10(1):3819. doi: 10.1038/s41467-019-11666-z.
Transit through the carbon liquid phase has significant consequences for the subsequent formation of solid nanocarbon detonation products. We report dynamic measurements of liquid carbon condensation and solidification into nano-onions over ∽200 ns by analysis of time-resolved, small-angle X-ray scattering data acquired during detonation of a hydrogen-free explosive, DNTF (3,4-bis(3-nitrofurazan-4-yl)furoxan). Further, thermochemical modeling predicts a direct liquid to solid graphite phase transition for DNTF products ~200 ns post-detonation. Solid detonation products were collected and characterized by high-resolution electron microscopy to confirm the abundance of carbon nano-onions with an average diameter of ∽10 nm, matching the dynamic measurements. We analyze other carbon-rich explosives by similar methods to systematically explore different regions of the carbon phase diagram traversed during detonation. Our results suggest a potential pathway to the efficient production of carbon nano-onions, while offering insight into the phase transformation kinetics of liquid carbon under extreme pressures and temperatures.
通过碳液相的过程对随后固体纳米碳爆轰产物的形成具有重大影响。我们通过分析在无氢炸药DNTF（3,4-双（3-硝基呋咱-4-基）呋咱）爆轰过程中获取的时间分辨小角X射线散射数据，报告了在约200纳秒内液态碳冷凝并固化为纳米洋葱的动态测量结果。此外，热化学模型预测DNTF产物在爆轰后约200纳秒会发生从液态到固态石墨的直接相变。收集了固体爆轰产物并用高分辨率电子显微镜进行表征，以确认平均直径约为10纳米的碳纳米洋葱的丰度，这与动态测量结果相符。我们用类似方法分析其他富碳炸药，以系统地探索爆轰过程中所穿越的碳相图的不同区域。我们的结果表明了一条高效生产碳纳米洋葱的潜在途径，同时深入了解了极端压力和温度下液态碳的相变动力学。
