Exploring Structural and Energetic Features of Energetic Salts Derived from 1-(Dinitromethyl)-5-(Nitroimino)-1,2,4-Triazole-3-Carboxylic Acid

Abstract Polynitro-1,2,4-triazole-based energetic materials have drawn widespread attention owing to their excellent oxygen balance along with superior detonation performance. The stability of such compounds can be significantly enhanced through salt formation. In this work, four high-energy ionic salts were prepared using 1-(dinitromethyl)-5-(nitroimino)-1,2,4-triazole-3-carboxylic acid (DNTC) as the precursor. The whole set of these ionic salts exhibited favorable thermal and mechanical stabilities (IS ≥ 25 J, FS ≥ 240 N, Td ≥ 183 °C). Among them, salts 5 and 7 demonstrated insensitive behavior. The nonmetal salts 8 and 9 showed good detonation properties, with detonation velocities (Dv) exceeding 8700 m s–1, comparable to that of hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX). These balanced physical properties are attributed to the sufficient energetic groups, the stabilizing effect of the carboxyl group, and the abundant hydrogen-bonding or coordination interactions introduced via salt formation. Single-crystal X-ray diffraction was used to determine the crystal structures of all newly synthesized ionic salts (5, 7–9). This work provides a novel strategy for designing highly energetic yet stable materials by synergizing stabilized carboxylic acid unit with high-energy polynitro-1,2,4-triazole motif.