Valence-Oriented Electrosynthesis Strategies of Cu-Based 5-Nitrotetrazolate for Environmentally Acceptable Primary Explosives

The development of green primary explosives has become a "holy grail" of energetic materials research. Cu-based 5-nitrotetrazolate is considered one of the most promising candidates due to its excellent blasting power and environmentally benign nature. However, synthesizing Cu-based 5-nitrotetrazolate controllably and securely remains highly challenging. Herein, room-temperature anodization of metallic Cu and a Cu(I)-imidazole nanowire array on copper substrates in a sodium 5-nitrotetrazolate electrolyte leads to in situ electrosynthesis of Cu(I) 5-nitrotetrazolate (DBX-1, CuNT) and its analogue, Cu(II) 5-nitrotetrazolate [Cu(NT)2], respectively. Both obtained CuNT and Cu(NT)2 films demonstrate remarkable energy output and good laser-induced ignition performance. The thermal stability (Tp = 291 °C) and electrostatic safety (E50 = 2.54 mJ) of CuNT proved to be superior to those of Cu(NT)2 (Tp = 257 °C, and E50 = 0.57 mJ). Remarkably, this study provides an exciting new method for the rational design and development of Cu-based 5-nitrotetrazolate as a primary explosive for advanced initiating applications.