Research into next-generation propellants with green fuel–oxidizer pairs to replace the currently used highly toxic hydrazine–NO system has attracted widespread attention. Ionic liquids (ILs) and hydrogen peroxide have demonstrated their feasibility as a green fuel and an oxidizer, respectively. However, the realisation of effective auto-ignition is the key problem. In this study, a new strategy to trigger the auto-ignition of ILs fuels with hydrogen peroxide by using a unique copper-containing liquid as the promoter is developed. The copper-containing promoter is designed such that its cationic structure is similar to that of the ILs fuels. Based on the principle of “like dissolves like,” the fuel and promoter can be miscible at any ratio to eventually form a catalytic fuel. In addition, the physicochemical properties (e.g. density, viscosity and decomposition temperature) and performance parameters (e.g. ignition delay time and specific impulse) of the as-prepared catalytic fuel are completely characterised. Owing to their excellent hypergolic performance with a short ignition delay time of 16 ms, in combination with the advantages of simple preparation, perfect solubility and green characteristics, the catalytic fuel–oxidizer pair demonstrates promise as bipropellants for rocket applications.

中文翻译：

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含铜液体助催化剂引发过氧化氢离子液体燃料自燃

以绿色燃料-氧化剂对替代目前使用的剧毒肼-NO系统的下一代推进剂的研究引起了广泛关注。离子液体（IL）和过氧化氢已分别证明其作为绿色燃料和氧化剂的可行性。然而，实现有效的自动点火是关键问题。在这项研究中，开发了一种通过使用独特的含铜液体作为促进剂来触发过氧化氢离子液体燃料自燃的新策略。含铜促进剂的设计使其阳离子结构与离子液体燃料的阳离子结构相似。基于“相似相溶”的原理，燃料和促进剂可以以任意比例混溶，最终形成催化燃料。此外，所制备的催化燃料的物理化学性质（例如密度、粘度和分解温度）和性能参数（例如点火延迟时间和比冲）被完全表征。由于其优异的自燃性能和 16 ms 的短点火延迟时间，结合制备简单、完美的溶解性和绿色特性的优点，催化燃料-氧化剂对显示出作为火箭应用双组元推进剂的前景。