Oxygen-Enriched Metal–Organic Frameworks Based on 1‑(Trinitromethyl)‑1<i>H</i>‑1,2,4-Triazole-3-Carboxylic Acid and Their Thermal Decomposition and Effects on the Decomposition of Ammonium Perchlorate

Energetic
metal–organic frameworks (EMOFs) with a high oxygen
content are currently a hot spot in the field of energetic materials
research. In this article, two series of EMOFs with different ligands
were obtained by reacting 1-(trinitromethyl)-1H-1,2,4-triazole-3-carboxylic
acid (tntrza) with metal iodide and metal nitrate, respectively. Furthermore,
their structure, thermal stability, thermal decomposition kinetics,
and energy performance are fully characterized. The research results
revealed that the synthesized EMOFs possess a wide range of density
(ρ = 1.88∼2.595 g cm–3), oxygen balance
(OB­(CO2) = −21.1∼ −4.3%), and acceptable
energy performance (D = 7.73∼8.74 km s–1 and P = 28.1∼41.1 GPa). The
difference in OB­(CO2) caused by the ligand structure and
metal properties has a great impact on the distribution of gas-phase
products after the decomposition of these EMOFs. Noteworthy, [Ag­(tntrza)]n is particularly prominent among these EMOFs,
not only because of its excellent detonation performance (D = 8.74 km s–1 and P = 41.1 GPa) endowed by its extremely high density (ρ = 2.595
g cm–3) and oxygen balance (OB­(CO2) =
−4.3%) but also because of its effective catalytic effect on
the decomposition of ammonium perchlorate (AP). This article broadens
the horizon for the study of oxygen-enriched EMOFs with catalytic
effects and helps understand the mechanism of thermal decomposition
of EMOFs with nitroform and dinitro groups.