Synthesis, crystal structure and properties of 3-picrylamino-1,2,4-triazole-nitric acid self-assembled energetic material

Abstract

The oxygen balance (OB) of energetic materials plays a critical role in determining the efficiency and effectiveness of energy release during combustion or detonation. To enhance the OB and comprehensive properties of 3-picrylamino-1,2,4-triazole (PATO), which is a high-energy and low-sensitivity explosive, this study employed a self-assembly strategy to combine nitric acid with PATO, resulting in a novel 3-picrylamino-1,2,4-triazole-nitric acid self-assembled energetic material (PATO-N). Its structure was characterized by single crystal X-ray diffraction, and the thermal decomposition properties and impact sensitivity were measured. The detonation performances were predicted by EXPLO5 and the OB was calculated based on its molecular formula. The results indicate that the self-assembly of PATO and HNO₃ effectively enhanced the explosive's OB (−67.7% to −44.6%)and promoted the completeness of the detonation reaction. PATO-N exhibits good thermal stability with an improved decomposition temperature of 315.9 °C. Its theoretical detonation velocity is 7.8 km s⁻¹, while the detonation pressure is 25.2 Gpa. PATO-N exhibited an impact sensitivity (H₅₀) exceeding 112.2 cm, classifying it as an insensitive energetic material.