PROCEEDINGS OF THE RUSSIAN HIGHER SCHOOL
ACADEMY OF SCIENCES

With the rapid development of space technology, the scale of human space exploration is expanding significantly. However, the growing demand for deep space travel cannot be met with conventional chemical engines. Thus, the need for new mechanisms for providing jet thrust, including electric motors, becomes clear. Electric propulsion technology has significant advantages over traditional chemical engines in deep space flight due to its characteristics such as high specific impulse, small size, long service life. A negative feature of electric motors can be called low thrust, however, firstly, in open space this is insignificant and, secondly, the thrust of electric motors can be significantly increased, and for this, there are reserves available at the current level of technology development. Ways to increase the thrust of electric ion thrusters will be detailed and discussed in this work. The increase in the power of ion engines is limited to a large extent by the erosion of the control grids, the ion flow hits the surface of the solid material of the control grid electrode with energetic ions and gradually leads to the failure of this electrode. In this work, the authors will show that the use of field emission as a source of electron beams ionizing the working medium can solve the problem of erosion of control electrodes, due to which it will be possible to significantly increase the strength of the working fields for ion engines, which in turn will increase the specific impulse, efficiency, flow rate and power of the ion engine as a whole.

1. Koroteev A.S. Lovtsov A.S., Muravlev V.A., Selivanov  M.Y., Shagayda A.A. Development of ion thruster IT-500. The European Physical Journal D, 2017, vol. 71, p. 120. DOI: 10.1140/epjd/e2017-70644-6.
2. Rovey J.L., Lyne C.T., Mundahl A.J., Rasmont N., Glascock M.S., Wainwright M.J., Berg S.P. Review of multimode space propulsion. Progress in Aerospace Sciences, 2020, vol. 118, p. 100627.
3. Okada T., Binzel R.P., Connolly H.C., Yada T., Ohtsuki K. Special issue “Science of solar system materials examined from Hayabusa and future missions (II)”. Earth, Planets and Space, 2017, vol. 69, p. 31. DOI: 10.1186/s40623-017-0617-3.
4. Sarli B.V., Yuichi T. Hayabusa 2 extension plan: Asteroid selection and trajectory design. Acta Astronautica, 2017, vol. 138, pp. 225–232.
5. Cherkun O., Demet U. Cesium hollow cathode with internal discharge and gas feed for electric propulsion applications. The 35th International Electric Propulsion Conference, Georgia Institute of Technology, 2017.
6. Shoor B., Davidson A., Lev D., Appel L., Epstein O., Herscovitz J. The Rafael Power Processing Unit (PPU) for electric propulsion systems. International Electric Propulsion Conference, Austria, University of Vienna, 2019.
7. Manente M., Trezzolani F., Magarotto M., Fantino E., Selmo A., Bellomo N., Toson E., Pavarin D. REGULUS: A propulsion platform to boost small satellite missions. Acta Astronautica, 2019, vol. 157, pp. 241–249.
8. Andrews R., Jacques D., Qian D., Rantell T. Multiwall carbon nanotubes: Synthesis and application. Accounts of Chemical Research, 2002, vol. 35 (12), pp. 1008–1017.
9. Platin E., Tucker A., Zhou O., Lu J. Stationary intraoral digital tomosynthesis using carbon nanotubes field emission x-ray technology: Clinical prototype. Oral Surgery, Oral Medicine, Oral Pathology and Oral Radiology, 2020, vol. 130 (2), p. e66.
10. Xu S., Li Y., Zou H., Qiu J., Guo Z., Guo B. Carbon nanotubes as assisted matrix for laser desorption/ionization time-of-flight mass spectrometry. Analytical Chemistry, 2003, vol. 75 (22), pp. 6191–6195.
11. Tsai J.T.H., Peng J., Chu K., Chen J.S. Performances improvement of vacuum tubes using carbon nanotubes embedded cathodes. Vacuum, 2017, vol. 145, pp. 1–3.
12. Evtukh A., Grygoriev A., Litovchenko V.G., Pylypova O. Influence of the emitted electron energy distribution from nanocathodes upon the current-voltage characteristics. Journal of Vacuum Science and Technology B, 2014, vol. 32 (2), pp. 02B104–02B104-4.
13. Litovchenko V., Evtukh A., Grygoriev A. Characterization of GaN nanostructures by electron field and photo-field emission. Opto-Electronics Review, 2017, vol. 25 (3), pp. 251–262.
14. Forman R. Evaluation of the emission capabilities of Spindt-type field emitting cathodes. Applications of Surface Science, 1983, vol. 16 (1–2), pp. 277–291.
15. Qiu J., Baturin S.S., Kovi K.K., Chubenko O., Chen G., Konecny R., Antipov S., Sumant A.V., Jing C., Baryshev S.V. Nanodiamond thin film field emitter cartridge for miniature high-gradient radio frequency X-band electron injector. IEEE Transactions on Electron Devices, 2018, vol. 65 (3), pp. 1132–1138.
16. Kyritsakis A., Veske M., Eimre K., Zadin V., Djurabekova F. Thermal runaway of metal nano-tips during intense electron emission. Journal of Physics D: Applied Physics, 2018, vol. 51 (22), p. 225203.
17. Egorov N.V., Sheshin E.P. On the current state of field-emission electronics. Journal of Surface Investigation: X-ray, Synchrotron and Neutron Techniques, 2017, vol. 11 (2), pp. 285–294.
18. Èidelman E.D., Arkhipov A.V. Field emission from carbon nanostructures: Models and experiment. Physics-Uspekhi, 20202, vol. 63 (7), p. 648.
19. Marrese C.M. A review of field emission cathode technologies for electric propulsion systems and instruments. 2000 IEEE Aerospace Conference. Proceedings, 2000, vol. 4, pp. 85–98.
20. Marrese-Reading C., Polk J., Mueller J., Owens A. In-FEEP thruster ion beam neutralization with thermionic and field emission cathodes. 27th International Electric Propulsion Conference, Pasadena, 2001.
21. Takao Y., Kugimiya A., Nagai S., Yamamoto N., Nakashima H. Development of neutralizer with carbon nanotube cathode for small scale ion engine. 30th International Electric Propulsion Conference, Florence, Italy, 2007.
22. Velásquez-García L.F., Akinwande A.I. A MEMS CNT-based neutralizer for micro-propulsion applications. 30th International Electric Propulsion Conference, Florence, Italy, 2007.
23. Yamamoto N., Morita T., Ohkawa Y., Nakano M., Funaki I. Ion thruster operation with carbon nanotube field emission cathode. Journal of Propulsion and Power, 2019, vol. 35 (2), pp. 490–493.
24. Ohkawa Y., Kawamoto S., Okumura T., Iki K., Okamoto H., Inoue K., Uchiyama T., Tsujita  D. Review of KITE–Electrodynamic tether experiment on the H-II Transfer Vehicle. Acta Astronautica, 2020, vol. 177, pp. 750–758.