Mixed-Metallic Energetic Metal–Organic Framework: New Structure Motif for Potential Heat-Resistant Energetic Materials

The incessant pursuit of heat-resistant explosives with balanced energetic performance and safety is indispensable in civil and military sectors, particularly when employed in harsh environments. Herein, a new nanostructured highly energetic metal–organic framework (E-MOF), based on nickel(II) and sodium(I) mixed-metal has been constructed using an energetic poly tetrazole molecule by the hydrothermal approach. The Na/Ni-MOF was thoroughly characterized using infrared radiation (IR), thermogravimetric analysis and differential scanning calorimetry, scanning electron microscopy, and powder X-ray diffraction analyses. Further, the crystal structure was authenticated by single crystal X-ray diffraction analysis, and their crystal packing features were well explored, revealing a wave-like 3D framework having a crystal density of 1.985 g cm–3. This mixed-metallic E-MOF demonstrated a good enthalpy of combustion (−7.91 kJ·g–1), a good velocity of detonation (VOD = 7410 m s–1) exceeding that of trinitrotoluene (TNT, 6820 m/s) and Hexanitrostilbene (HNS, 7164 m/s), and excellent insensitivity [impact sensitivity (IS) > 40 J and friction sensitivity (FS) > 360 N]. Additionally, it exhibits outstanding thermal stability (Td = 387 °C). These fine-tuned properties are superior to those of continuously used benchmark heat-resistant explosives HNS and 2,4,6-triamino-1,3,5-trinitrobenzene, suggesting that the newly reported poly tetrazole-based E-MOF is beneficial for improved physical performance. The results given in the present work highlighted the advantages of the mixed-metallic E-MOF as a potential heat-resistant explosive for future applications.