In Situ Synthesized MEMS Compatible Energetic Arrays Based on Energetic Coordination Polymer and Nano-Al with Tunable Properties

Abstract

Integrating energetic materials with a microelectromechanical system (MEMS) to achieve miniaturized integrated smart energetic microchips is promising. The potential applications include actuation in lab-on-a-chip devices, ignition in automobile airbags, propulsion and attitude control of micro-/nano-satellites, and miniaturized electro-explosive devices. In this work, a new type of MEMS-compatible energetic arrays was in situ realized on a copper substrate, which comprised a new energetic coordination polymer (ECP; Cu 1.5 C 2 N 8 O 2 •H 2 O) with tunable nanostructures and a nanoaluminum (nano-Al) covering layer. The composition, morphology, and energetic characteristics of the energetic arrays can be easily tuned by adjusting the reaction time. The maximum heat release of 1850.2 J/g in thermal analysis and the intense flame in open burning experiment proved its excellent exothermic and combustion performance. A closed-bomb experiment further revealed that the ECP@nano-Al energetic arrays supported on Cu(OH) 2 nanorods had a peak pressure (5.5 MPa) and a pressure duration (0.5 s) more than twice those of nanoscale Al/CuO powder because of the introduction of gas elements (e.g., C, H, and N). A preliminary impulse experiment was also conducted through the torsion pendulum method. The displacement of the torsion pendulum in the micrometer scale proved the potential application of the energetic arrays in micropropulsion systems. Overall, this work can serve as a reference for the synthesis and applications of ECPs.

Efficient Synthesis of Nanoscale Cadmium Azide from Intercalated Cadmium Hydroxide for Nanoexplosive Applications

“…Aerospace and weapon systems are developing toward integration, compactness, and miniaturization. Microinitiating devices, the initial energetic elements of the systems, have a wide application in explosive systems. − The primary explosive is a substance that can achieve deflagration to detonation in an extremely short time under the stimulation of tiny external energy to detonate secondary explosives. It is the most initial, most sensitive, and cost-effective starting energetic material of aerospace and weapon systems and is the heart of initiating devices. − …”

A Highly Effective Liquid–Solid Reaction for In Situ Preparation of Copper Azide

“…In addition, the sensitivities and ignition test of the CA film were characterized. The electrostatic discharge sensitivity of the CA film was obtained by the equation E = 1/2CV 2 , where E corresponded to the electrostatic energy (J), C corresponded to the capacitance of the capacitor (F), and V corresponded to the charge voltage (V). The E result for a 50% probability of ignition of CA is 0.42 mJ, which was three times more than the original CA powder (0.13 mJ) and showed an improved safety.…”

“…A microinitiator combined with microelectromechanical systems (MEMS) has attracted much interest owing to its integration and miniaturization, showing promising application prospects in aerospace, automobile airbags, and weapons. − Primary explosives, as the energy output source, play a crucial role in microinitiator. Nowadays, the miniaturization of initiator has put high requirements on the performances of primary explosives.…”

Core–Shell Copper Azide-Based Nanofiber Films Prepared by Coaxial Electrospinning for MEMS Microinitiators

“…Because of the miniaturization and dexterity of weapon and ammunition systems, the microinitiator is a critical component of the up-and-coming age of microelectromechanical systems (MEMS). − As the core component of the microinitiator, the micro-nano structure primary explosive plays an important role. Azide with excellent detonation performance mainly includes lead azide (LA), copper azide (CA), silver azide (SA), etc., among which lead azide and silver azide are no longer suitable for practical needs due to high cost, pollution, and other reasons. − However, copper azide is harmless to the ecosystem, and only a very small amount of charge can trigger secondary explosives, which has a very good application potential.…”