Electrochemical Modulation of the Flammability of Ionic Liquid Fuels

Flammability and combustion of high energy density liquidpropellantsare controlled by their volatility. We demonstrate a new concept throughwhich the volatility of a high energy density ionic liquid propellantcan be dynamically manipulated enabling one to (a) store a thermallyinsensitive oxidation resistant nonflammable fuel, (b) generate flammablevapor phase species electrochemically by applying a direct-currentvoltage bias, and (c) extinguish its flame by removing the voltagebias, which stops its volatilization. We show that a thermally stableimidazolium-based energy dense ionic liquid can be made flammableor nonflammable simply by application or withdrawal of a direct-currentbias. This cycle can be repeated as often as desired. The estimatedenergy penalty of the electrochemical activation process is only & SIM;4%of the total energy release. This approach presents a paradigm shift,offering the potential to make a safe fuel or alternativelya simple electrochemically driven fuel metering scheme.

Automated summary

The volatility of a high energy density ionic liquid propellant can be manipulated to store a nonflammable fuel and generate flammable vapor species electrochemically. This approach offers the potential for safe fuel storage and simple electrochemically driven fuel metering.