Field emission cathodes made from knitted carbon nanotube fiber fabrics

• DOI: 10.1063/5.0123120
• Publication Date: 2023-03-01T10:45:13Z
• Authors: Steven B. Fairchild; Chelsea E. Amanat...; Thiago A. de Assis; Paul T. Murray; Dmitri Tsentalovich; Jeffrey L. Ellis; Salvador Portillo; Sushil R. Kanel; John S. Bulmer; Jeongho Park; Genevieve Dion; John J. Boeckl
• Keywords: Field emission microscopy

Field electron emission cathodes were constructed from knitted fabrics comprised entirely of carbon nanotube (CNT) fibers. The consisted a top layer array ∼2 mm high looped structures and bottom that was 1 thick with flat underlying surface. (FE) experiments performed on 25.4 diameter CNT fabric in both direct current (DC) pulsed voltage (PV) modes, the results compared to those obtained film cathode. DC measurements at maximum 1.5 kV. cathode emitted 20 mA, which an 8× increase over analyzed using corrected form Fowler–Nordheim FE theory initially developed by Murphy Good, allows for determination formal area effective gap-field enhancement factor. PV resulted Ampere level currents cathodes. For 25 kV, 500 ns pulse, 4 A, 2× more than Scanning microscopy imaging after testing revealed fibers remained intact >5000 pulses. These indicate offer promising approach developing large area, conformable, robust vacuum electronic devices.