Exploring the Maximum Potential of Initiating Ability in Metal-Free Primary Explosives

Lead azide (LA) is a widely utilized primary explosive, serving as the initiating charge in blasting caps or detonators to start the detonation process of secondary explosives. The toxicity and environmental concerns associated with LA have led to regulatory restrictions and increased scrutiny, prompting the search for lead-free alternatives. LA is highly sensitive toward heat, shock, or friction, which poses safety challenges during manufacturing, handling, and storage. Developing lead-free, environmentally friendly, thermostable, and safe next-generation primary explosives with high initiating ability is a significant challenge and an important goal. Herein, 1,8-diazido-bis([1,2,4]triazolo)[4,3-b:3',4'-f][1,2,4,5]tetrazine (DATTY) was synthesized and studied. It is important to highlight that DATTY has a high nitrogen content of 80.3%, and a lower friction sensitivity (5 N) than that of LA (0.3 N), while being stable under ambient conditions. DATTY is a highly endothermic primary explosive with a heat of formation of 6.533 kJ g-1. It demonstrates exceptional initiating ability, with a minimum primary charge (MPC) of just 1 mg, markedly lower than the MPC of LA, which is 10 mg, as well as other previously reported primary explosives. The detonation velocity of DATTY (vD = 8835 m s-1) is exceptional, surpassing that of all other primary explosives. The development of DATTY represents significant progress in the field of primary explosives, setting a new benchmark for safety and efficiency.