Construction of High Energy Nanoscale Lead Azide Composite with Improved Flame Sensibility from Intercalated Hydroxide

Abstract

It is of great significance to develop efficient methods for preparing high-content modified nanoscale lead azide (LA) composites used in microinitiating devices. In this work, a structurally controllable salicylateintercalated lead hydroxide with a nanoscale mesoporous structure is designed. Using it as a precursor, carbon-based lead azide (LA/C) and salicylate-based lead azide (LA/SA) are fabricated by the gas−solid azidation of the framework (GAF) method within 3 h, greatly reducing the preparation time of nano-LA composites. The characterizations of the composites demonstrate that the Pb in the precursors is transformed into nanoscale LA attached to the salicylate radical or its carbonized skeleton. Due to the unique embedded nanostructures and excellent electrical and thermal conductivity of salicylate-derived carbon materials, LA/C exhibits excellent electrostatic safety (E 50 = 0.25 J) and flame sensitivity (H 50 = 28 cm). The adjustable organic−inorganic ratio of intercalated hydroxides allows the LA content in LA/C to reach as high as 92.5%, enabling 6.50 mg of LA/C to successfully detonate secondary explosive CL-20 in a microinitiating device, demonstrating an amazing detonation ability superior to other reported LA complexes. The research provides a new perspective for the development of nanoscale LA composites with high LA content and appropriate sensitivity.

Study on the Effect of Nanoporous Copper Particle Size on Copper-Based Azide

“…where ρ is the loading density of copper powder, g•cm 3 , and in the experiment, the molding density of the samples was about 1.45 g•cm −3 . M is the molar mass, g/mol, and the molar mass of Cu was 63.55 g/mol; ∆ f H 0 m is the standard molar enthalpy of the generation of the substance, kJ/mol, in which the standard molar enthalpies of generation of Cu, CuN 3 and Cu(N 3 ) 2 were 0, 281 and 587 kJ/mol [20]; E v is the energy density per unit volume, J/mm 3 ; and α denotes the conversion rate.…”

“…In recent years, micro-initiators developed on the basis of Micro-Electro-Mechanical Systems (MEMSs) have gained increasing attention due to their advantages of intelligence, mass production, low cost and high reliability [1]. The concern over environmental pollution caused by heavy metal ions in lead azide has been growing in recent years [2][3][4][5], and with the development of miniaturization in weapon systems, the output capacity of lead azide appears somewhat insufficient, potentially limiting its future applications [6,7].…”