Hollow Cathode

Gridded Ion Engines and Hall Effect Thrusters require Hollow Cathodes (HCs) to emit electrons that ionize the propellant forming the plasma and neutralize the positively charged ion beam.
 

Mars Space Ltd is currently developing its own range of Hollow Cathodes for laboratory use. These cathodes utilize an advanced heater technology and lanthanum hexaboride (LaB6) inserts for increased reliability, robustness and ease of use.

​MSL hollow cathodes are designed to deliver the following flexible performance:   

• Discharge Current: in the range 1.5 - 40 A
• Operating Voltage: 15  - 21 V
• Heater Power: 100 W​

The main advantages of the MSL HC design are:​​

1. little to no susceptibility to oxygen poisoning 
2. much lower gas-fed impurity level requirement when compared to impregnated cathodes
3. No outgassing procedure required after exposure to air
4. robust heater desing that does not suffer from embrittlement
5. simple and modular design