Contemporary electric thrusters utilize hollow cathodes as electron emitters. These cathodeshave long activation time and limited number of ignitions. As an alternative field emissioncathodes are now being considered, enabling instantaneous ignition and offer power andpropellant savings. However, difficulties arise when such cathodes are required to be operated atlow voltage as required in Hall thrusters. In the present paper new approach to the design of suchcathodes is developed. An acceleration-deceleration electrode system is considered, where a highpotential electrode provides the electric field necessary for carbon nanotubes to emit; followedby a second electrode which decelerate the electrons. To mitigate power loss due to returningcurrents a multi aperture cathode is considered together with ionization of propellant. 2D axialsymmetric simulations of a single sub-cathode were carried out using the particle-in-cellcomputer program (OOPIC), modeling field emission and the ionization of Xenon gas. 1 Acathode with 1000 apertures, is shown to cover an area of ～20 cm 2 with mass <10 gram. Thecathode requires Xenon mass flow rate of 0.11 mgram/sec and 15 W of power to operate,comparable to an advanced hollow cathode, but enables virtually instantaneous ignition andpossible longer lifetime.
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