Over the past century, the search for lead-free, environmentally friendly initiating substances has been a highly challenging task in the field of energetic materials. Here, an organic primary explosive featuring a fused-ring structure, 6-nitro-7-azido-pyrazol[3,4-d][1,2,3]triazine-2-oxide, was designed and synthesized through a facile two-step reaction from commercially available reagents. This organic initiating substance meets nearly all of the stringent criteria of environmentally friendly primary explosives for commercial applications: it is free of toxic metals and perchlorate, has a high density, high priming ability, unusual sensitivities towards non-explosive stimuli, excellent environmental resistance, decent thermal stability, high detonation performance, satisfactory flowability and pressure durability, and is low-cost and easy to scale-up. These combined properties and performance measures surpass the current and widely used organic primary explosive, DDNP. The fused-ring organic primary explosive reported herein may find real-world application as an initiating explosive device in the near future.

Reaching the goal of developing an insensitive high-energy molecule (IHEM) is a major challenge. In this study, 3,5-diamino-6-hydroxy-2-oxide-4-nitropyrimidone (IHEM-1) was synthesized in one step from 2,4,6-triamino-5-nitropyrimidine-1,3-dioxide hydrate (ICM-102 hydrate). The density of compound IHEM-1 is 1.95 g cm–3 with a decomposition temperature of 271 °C. Its detonation velocity and pressure are 8660 m s–1 and 33.64 GPa, respectively, which are far superior to the detonation performance of 1,3,5-triamino-2,4,6-trinitrobenzene (TATB), while its sensitivity is identical with that of TATB. In addition, four derivatives (1a, chloride; 1b, nitrate; 1c, perchlorate; and 1d, dinitramide) were prepared on the basis of the weak base site (N–O group) and show excellent energetic properties. By combining a series of advantages, including simple preparation, high yield, high density, very low solubility in aqueous solution, high thermostability, insensitivity, and excellent detonation performance, IHEM-1 approaches an ideal insensitive high-energy molecule. Compounds 1b–1d are also competitive as new high-energy-density materials.

Two 5,6-fused tetrazolo-pyridazine compounds were synthesized and characterized, which exhibited high thermal stability, excellent energetic properties and low mechanical sensitivity.

Owing to its simple preparation and high oxygen content, nitroformate [−C(NO2)3, NF] is an extremely attractive oxidant component for propellants and explosives. However, the poor thermostability of NF-based derivatives has been an unconquerable barrier for more than 150 years, thus hindering its application. In this study, the first example of a nitrogen-rich hydrogen-bonded organic framework (HOF-NF) is designed and constructed through self-assembly in energetic materials, in which NF anions are trapped in pores of the resulting framework via the dual force of ionic and hydrogen bonds from the strengthened framework. These factors lead to the decomposition temperature of the resulting HOF-NF moiety being 200 °C, which exceeds the challenge of thermal stability over 180 °C for the first time among NF-based compounds. A large number of NF-based compounds with high stabilities and excellent properties can be designed and synthesized on the basis of this work.

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Eco-friendly high-energy-density materials with remarkably high nitrogen contents and heats of detonation are achieved based on an anionic MOF strategy. Meanwhile, their stabilities and insensitivities are well improved by hydrogen bonds.

Energetic metal−organic frameworks (E-MOFs) have witnessed increasing development over the past several years. However, as a highly energetic cation, NH 3 OH + has never been explored to construct transition-metal-based E-MOFs. Herein, we report the first examples of NH 3 OH + -containing E-MOFs with bis(tetrazole)methane (H 2 btm) as a ligand and copper and manganese as central metal ions, [(NH 3 OH) 2 (Cu-(btm) 2 )] n and [(NH 3 OH) 2 (Mn(btm) 2 )] n . Crystal structure determinations reveal that both E-MOFs show two-dimensional layered structures. Experimental results suggest that they have high thermal decomposition temperatures (>200 °C). Among them, Cu-based E-MOFs possesses outstanding thermal stability (T dec = 230.3 °C), which surpasses those of known NH 3 OH + -containing compounds. They also have high energy density; in particular, the Cu-based E-MOF affords a high heat of combustion (11447 kJ kg −1 ) and high heat of detonation (713.8 kJ mol −1 ) beyond the most powerful organic explosives in use today. Additionally, the two E-MOFs show completely different sensitivity properties: the Mn-based E-MOF is an insensitive high-energy-density material (IS > 40 J; FS > 360 N; EDS > 20 J), while the Cu-based E-MOF can be classified as a sensitive energetic material (IS = 13 J; FS = 216 N; EDS = 10.25 J), demonstrating their diverse applications in different fields. Our research proposes a unique class of high-energy-density materials.

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