A study of two metal energetic complexes based on 4-amino-3-(5-tetrazolate)-furazan: synthesis, crystal structure, thermal behaviors and energetic performance

Abstract In this contribution, two metal energetic complexes Co(HCONHNH2)2(AFT)2·H2O (1) and [Pb(HCONHNH2)2(AFT)2]n (2) (HCONHNH2=formyl hydrazide and HAFT = 4-amino-3-(5-tetrazolate)-furazan) have been synthesized and characterized. The structures of compound 1 and 2 are characterized by single crystal X-ray diffraction. The tests show that 1 possesses One-dimensional (1D) chain structure and 2 exhibits two-dimensional (2D) energetic metal-organic framework (MOF). The thermal decomposition processes of compounds have been investigated by MS-FTIR-DSC-TG coupling technique. It's worth noting that both of them exhibit higher thermal stabilities. Moreover, gaseous products generated after thermal decomposition of compound 1 and 2 are CO2, NO2, N2O, CO, HCN, NH3, H2O, N2. The standard molar enthalpies of formation of 1 and 2 are calculated to be -4501.25 kJ·mol-1 and -1091.13 kJ·mol-1, respectively. Detonation velocity and detonation pressure are respectively 9.32 km·s−1, 42.13 GPa for 1 and 5.62 km·s−1, 18.36 GPa for 2. Surprisingly, compound 2 exhibits promising detonation velocity and detonation pressure, which are higher than those of TNT, RDX and HMX. The above-mentioned information on thermal behavior is available to analyze and evaluate the stability and thermal safety of 1 and 2. The sensitivity tests reveal they possess excellent insensitivities to impact and friction. All the characterizations show that they can be used as potential energetic materials.