Fabrication of Copper Azide Film through Metal-Organic Framework for Micro-Initiator Applications

The paradox between safety and detonation performance, along with the intrinsic fragility of primary explosives, is the main bottleneck precluding their application in a micro-initiation system. To tackle these issues, we fabricate a flexible copper azide film (CA-C film@PF) via employing the metal-organic framework (MOF) film produced by electrospinning technique as the precursor, followed by pyrolysis treatment, in situ azide reaction, and perfluorinated coating procedures. The synergetic effect of MOF and interweaved polymer fiber endow the resultant copper azide film with excellent electrostatic stability and remarkable detonation performance. In particular, the electrostatic discharge sensitivity (E-50) value (9 mJ) is 180 times higher than that of the original copper azide powder (0.05 mJ) and the static electricity accumulation value (-Q) is 430 times lower than that of copper azide powder (0.04 vs 17.2 nC g(-1)). As the proof of concept, the copper azide film is further assembled in a micro initiation device, which can successfully detonate the secondary explosives CL-20. Additionally, the superhydrophobic surface of the CA-C film@PF merit the initiation power even after being soaked in water.