New coordination complexes-based gas-generating energetic composites

Abstract

To reduce the size inconvenience of airbag systems employed in human-body protection devices while maintaining comparable gas generation performance, a new family of gas-generating energetic compos- ites are proposed mixing Al/CuO nanothermite with copper complex (Cu(NH3 )4 (NO3 )2 ) known for its propensity to generate gases (0.03 mol/g) such as N2 , O2 , N2 O through exothermic chemical decomposi- tion (300 J/g). The aluminum (Al)/Copper oxide (CuO) couple, known as the most widely studied nanoma- terial for thermite reactions, releasing a high energy, mostly heat, through chemical reaction, is employed as a source of heat to trigger and sustain the decomposition of Cu(NH3 )4 (NO3 )2 complex. This work per- mits developing a new family of gas-generating energetic composites that takes advantage of specific chemical and thermal properties of both materials. We demonstrate its capability to tune the pressuriza- tion rate, burn rate and pressure peak by varying the Al/CuO over Cu(NH3 )(NO2 )2 mass ratio. The peak pressure of Cu(NH3 )4 (NO3 )2 /Al/CuO energetic composites reaches 12 MPa/g.cm3 in a close volume, which is 3.3 higher than that of traditional Al/CuO nanothermite. They achieve much longer high-pressure dura- tion ( ∼30 ms). They also exhibit very intense burning with velocity reaching hundreds of m/s in opening burning experiments. These new materials appear very promising for green gas generation.