Hunting for Energetic Complexes as Hypergolic Promoters for Green Propellants Using Hydrogen Peroxide as Oxidizer

The development of hypergolic materials has aroused great interest due to their important applications in aerospace technology. In this work, six new energetic complexes were prepared and comprehensively characterized. All energetic complexes had isostructural characteristics, which made them ideal candidates for studying their structure-performance relationships. These energetic complexes had good thermal stabilities and excellent specific impulses. The vacuum-specific impulses were in the range 264.0-271.9 s, which was greater than most reported solid hypergolic materials. Moreover, the hypergolic performance of these compounds was examined by using 100% HNO₃ as the oxidizer, and their catalytic performance in the hypergolic reaction of typical energetic ionic liquids and 90% H₂O₂ was comprehensively studied. All compounds displayed excellent hypergolic performance with the shortest ignition delay time of 4 ms. The examined copper-containing energetic complexes displayed excellent catalytic activities for the hypergolic reaction between energetic ionic liquids and 90% H₂O₂. The shortest ignition delay time of the examined hypergolic reactions was 31 ms. The suitable physicochemical properties, excellent energetic properties, and high catalytic activity of the hypergolic reactions have demonstrated the great potential of these energetic complexes as promoters for the development of green hypergolic bipropellants.