Nano-graphite field-emission cathode for space electric propulsion systems.

Area of Science:

• Spacecraft propulsion
• Materials science
• Plasma physics

Background:

• Improving thruster efficiency is critical for electric propulsion systems.
• Air-breathing thrusters use atmospheric gases as fuel, requiring efficient electron emission.
• Field emission (FE) cathodes offer high energy efficiency by avoiding heating.

Purpose of the Study:

• To investigate field emission from nano-graphite thin films.
• To assess their suitability for space electric propulsion systems.
• To design and demonstrate an electron gun utilizing these cathodes.

Main Methods:

• Fabrication and characterization of nano-graphite thin films.
• Experimental study of field emission properties under various gas pressures and current loads.
• Design and testing of an electron gun prototype.

Main Results:

• Nano-graphite films exhibited suitable field emission characteristics.
• Performance was validated across a range of gas pressures and in both constant and pulsed modes.
• The developed electron gun demonstrated increased reliability and minimized energy losses.

Conclusions:

• Nano-graphite thin films are a viable material for efficient field emission cathodes.
• The developed electron gun is suitable for air-breathing satellites in low Earth orbit.
• This technology contributes to more efficient and reliable space electric propulsion.