Constructing zero-valent nanotwinned copper for the ignition of [BMIM]N(CN)2–H2O2 green propellant†

The ionic liquid–H₂O₂ system is a green hypergolic propellant; however, its poor self-ignition performance hinders its application. Herein, a stable zero-valent Cu nanoparticle catalyst with twin boundaries (T-Cu) was synthesized. As the twin boundary regulates the electron micro-environment of the T-Cu surface, the electron transfer from the d electrons of the Cu atom to the σ* anti-bonding orbital of H₂O₂ is enhanced to create ˙OH and ˙OOH. The resulting free radicals possess a strong oxidizing ability and react violently with [BMIM]N(CN)₂ to achieve rapid ignition with a delay time as low as 25 ms. This work provides an effective method to ensure excellent ignition performance and promotes the application of ionic liquid–H₂O₂ green hypergolic propellants.