Ionic liquids are the base for electrospray propulsion, yet few have been explored. The performance of an externally wetted electrospray thruster is characterized for seven different ionic liquids: 1-ethyl-3-methylimidazolium tetrafluoroborate (EMI-B), dicyanamide (EMI-DCA), bistrifluoromethylsulfonylimide (EMI-Im), thiocyanate (EMI-SCN), ethylsulphate (EMI-EtOSO), triflate (EMI-OTf), and trifluoromethanesulfonate (EMI-TFA). This research marks the first time that the latter four liquids are reported for externally wetted emitters. A complete thruster assembly has been tested with each of the propellants. Using time-of-flight mass spectrometry and a Faraday cup for beam divergence, the performance of these ionic liquids has been characterized, assessing thrust, specific impulse and thrust efficiency. EMI-B, EMI-DCA and EMI-SCN operated in pure ionic regime while EMI-Im, EMI-EtOSO, EMI-OTf and EMI-TFA operated in mixed regime.

中文翻译：

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外部润湿电喷雾推进器离子液体的发射和性能表征

离子液体是电喷雾推进的基础，但很少有人进行过探索。外部润湿电喷雾推进器的性能针对七种不同的离子液体进行表征：1-乙基-3-甲基咪唑鎓四氟硼酸盐 (EMI-B)、二氰胺 (EMI-DCA)、双三氟甲基磺酰亚胺 (EMI-Im)、硫氰酸盐 (EMI-SCN) 、乙基硫酸盐 (EMI-EtOSO)、三氟甲磺酸盐 (EMI-OTf) 和三氟甲磺酸盐 (EMI-TFA)。这项研究标志着首次报道后四种液体用于外部润湿发射器。完整的推进器组件已经使用每种推进剂进行了测试。使用飞行时间质谱和用于光束发散的法拉第杯，对这些离子液体的性能进行了表征，评估了推力、比冲和推力效率。EMI-B、EMI-DCA 和 EMI-SCN 在纯离子状态下运行，而 EMI-Im、EMI-EtOSO、EMI-OTf 和 EMI-TFA 在混合状态下运行。