The design and synthesis of novel energetic compounds with integrated properties of high density, high energy, good thermal stability and sensitivities is particularly challenging due to the inherent contradiction between energy and safety for energetic compounds. In this study, a novel structure of 4-amino-7,8-dinitropyrazolo-[5,1-d] [1,2,3,5]-tetrazine 2-oxide (BITE-101) is designed and synthesized in three steps. With the help of the complementary advantages of different explosophoric groups and diverse weak interactions, BITE-101 is superior to the benchmark explosive HMX in all respects, including higher density of 1.957 g·cm⁻³, highest decomposition temperature of 295 °C (onset) among CHON-based high explosives to date and superior detonation velocity and pressure (D: 9314 m·s⁻¹, P: 39.3 GPa), impact and friction sensitivities (IS: 18 J, FS: 128 N), thereby showing great potential for practical application as replacement for HMX, the most powerful military explosive in current use.

A new N-functionalized strategy of nitrogen heterocycles was utilized for the synthesis of nitroazole-based energetic materials, giving rise to a new family of highly dense and oxygen-rich energetic materials. They were characterized by IR spectroscopy, NMR spectroscopy, elemental analysis, DSC, and X-ray diffraction. These new molecules exhibit high densities, moderate to good thermal stabilities, acceptable impact and friction sensitivities, and excellent detonation properties, which suggest potential applications as energetic materials or oxidizers. Interestingly, among tetrazole-based CHNO energetic materials compound 5 has the highest measured density of 1.97 g cm⁻³ to date. 5c is the first and the only heterocyclic CHNO energetic salt with a positive OB until now. Compounds 5 and 6 exhibit excellent detonation properties (38.5 GPa, 9.22 km s⁻¹; 37.0 GPa, 9.05 km s⁻¹), comparable to the highly explosive HMX. With high OB, the specific impulses of 5, 5b, 5c, and 6c are superior to those of AP and ADN as neat compounds, and the ratio of oxidizer/aluminium/PBAN (%) is 80 : 20 : 0 or 80 : 13 : 7. Furthermore, computational results, BDEs, Mulliken charges and Wiberg bond orders also support the superior qualities of the newly prepared compounds and the design strategy.

A novel high-nitrogen compound with an N,N′-azo linkage, 4,4′-azobis(1,2,4-triazole), has been synthesized and well characterized. The solid-state structure was determined by X-ray diffraction. The experimentally determined density and enthalpy of formation matched with theoretically computed values based on the B3LYP method. The DSC result suggests that 4,4′-azobis(1,2,4-triazole) decomposes at a relatively high temperature (313.36 °C). By comparison with 3,3′-azobis(1,2,4-triazole), containing a C,C′-azo linkage, the N,N′-azo linkage was found to provide compounds with a relatively high density and high energy.