New coordination complexes-based gas-generating energetic composites

International audienceTo 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 composites 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 N 2 , O 2 , N 2 O through exothermic chemical decomposition (300 J/g). The aluminum (Al)/Copper oxide (CuO) couple, known as the most widely studied nanomaterial 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 permits 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 pressurization 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.cm 3 in a close volume, which is 3.3 2 higher than that of traditional Al/CuO nanothermite. They achieve much longer high-pressure duration (~ 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