Field-ionization based electrical space ion thruster using a permeable substrate

A field-ionization based electrical thruster comprising:

• a gas propellant inlet configured to receive gas propellant from a source of gas propellant;
• a positive-ion field-ionization chamber;
• a porous plug, wherein said gas propellant inlet is in fluid communication with said positive-ion field-ionization chamber through said porous plug, and said porous plug is configured to disperse said gas propellant into said positive-ion field-ionization chamber;
• said positive-ion field-ionization chamber comprising a permeable ionizer substrate downstream in a flow wise direction from said porous plug, wherein said permeable ionizer substrate is configured to receive said gas propellant from said porous plug and to produce positive ions of said gas propellant and freed electrons by field ionization,
• a plurality of electrodes positioned downstream of said permeable ionizer substrate, said plurality of electrodes configured to receive said positive ions and to accelerate said positive ions away from said permeable ionizer substrate to produce an ion beam, wherein said plurality of electrodes comprises:
• at least one gate electrode;
• at least one lens electrode positioned downstream of said at least one gate electrode;
• and
• at least one accelerator electrode positioned downstream of said at least one lens electrode;
• a neutralizer positioned downstream of said plurality of electrodes, wherein said neutralizer is configured to electrically neutralize said ion beam;
• and
• an external circuit coupling said permeable ionizer substrate with said neutralizer, wherein said external circuit is configured to transfer said freed electrons from said permeable ionizer substrate to said neutralizer.