-Ignitophores.*

The race and competition in aerospace technologies based on environmentally friendly green propulsion systems with green fuels and oxidizers are attracting significant attention. The development of hybrid propulsion systems that use a hypergolic fuel and green H₂O₂ oxidizer, capable of deep throttling and restarting from “cold”, is a very challenging task. Here, we describe a new synthetic approach for the synthesis and characterization of conceptually new hydride- and boron-free, and air/moisture stable solid H₂O₂-hypergols, based on Cu and Co complexes of bis(5-tetrazolyl) amine (H₂BTA) ligand. Among prepared and evaluated materials, the best performing compound [K₂(H₂O)₂Cu(BTA)₂]n (JD-4) was found to exhibit a short ignition delay time of 7 ms (with H₂O₂, 97%), and a high thermostability of 343 °C. Based on obtained ignition results, X-ray crystallography, and HASEM software calculations, structure-hypergolic activity-relationship studies were conducted. We found that the electron density difference between Cu and BTA units should be in a specific range (~2) for these compounds to ignite, providing a valuable tool for further development of novel, green, solid fuels for propulsion systems.