Self-Assembly of Nitrogen-Rich Heterocyclic Compounds with Oxidants for the Development of High-Energy Materials

The development of energetic materials with high energy and low sensitivity has attracted immense interests due to their widespread applications in aerospace technology and national defense. In this work, a promising self-assembly strategy was developed to prepare three high-energy materials (1–3) through the introduction of oxidant molecules into the crystal voids of the parent materials. The structures of these new materials were comprehensively examined by infrared spectroscopy, nuclear magnetic resonance (NMR) spectroscopy, and single-crystal X-ray diffraction. In these materials, three unique layer structures with hcb, sql, and interrupted sql topologies were observed, which were formed by the fused-ring-based energetic components. Windows with hexagonal, square, and rectangular structures were observed within these layer structures, which were occupied by H2O2, NO3–, and ClO4–, respectively. Oxidant molecules interacted with parent molecules via hydrogen bonds to form crystal structures of these materials. Moreover, the energetic property of these materials was estimated by computing methods. The calculation results revealed that these self-assembly materials exhibit excellent energetic properties. The highest energetic performance was observed for compound 3. The detonation velocity, detonation pressure, and specific impulse values were up to 9339 m·s–1, 42.5 GPa, and 308 s, respectively, which were greater than those of HMX. Furthermore, these materials exhibited good sensitivity, which was closely related to their unique crystal structures. The high performance of these materials indicated that the self-assembly strategy should be a promising method for the development of novel energetic materials.

高能量低感度含能材料的开发因其在航空航天技术与国防领域的广泛应用而受到广泛关注。本研究开发了一种极具应用前景的自组装策略，通过将氧化剂分子引入母体材料的晶体空隙中，成功制备了三种含能材料（1~3）。通过红外光谱、核磁共振（Nuclear Magnetic Resonance, NMR）光谱以及单晶X射线衍射对这三种新型材料的结构进行了全面表征。在这些材料中，观察到三种由稠环含能组分构筑的独特层状结构，其拓扑类型分别为hcb、sql以及间断sql拓扑。上述层状结构中存在六边形、正方形与矩形窗口，分别被过氧化氢（H₂O₂）、硝酸根（NO₃⁻）以及高氯酸根（ClO₄⁻）所占据。氧化剂分子与母体分子通过氢键相互作用，构筑了该类材料的晶体结构。此外，通过计算方法对该类材料的含能性能进行了评估。计算结果表明，这些自组装材料展现出优异的含能性能，其中化合物3的性能最优。其爆速、爆压以及比冲最高分别可达9339 m·s⁻¹、42.5 GPa与308 s，均优于奥克托今（HMX）。此外，该类材料展现出良好的感度性能，这与其独特的晶体结构密切相关。该类材料的优异性能表明，自组装策略是开发新型含能材料的极具潜力的途径。