Triboelectric Nanogenerator Driven Carbon Nanotube Cathode: A Sustainable Self-Powering Electron Source

A field electron emitter is a promising cold electron source that can be applied in various vacuum micro/nanoelectronic apparatus. On the other hand, triboelectric nanogenerators (TENGs) harvest mechanical energy from the surroundings and convert it into electricity. Due to the high voltage and current generation, TENGs can be employed as a pulsed mode voltage source to extract electrons from field electron emitters. Herein, we have prepared high-performance carbon nanotube (CNT) emitters, which show low turn-on field (2.29 V μm–1, for achieving the current density of 1.0 mA cm–2), high current density (115 mA cm–2@4.00 V μm–1), prolonged emission stability (without remarkable deterioration lasting for 18.5 h), and homogeneous emission patterns. Apart from that, the CNT emitter is assembled with contact-separation mode TENG. The TENG-driven CNT emitter shows a sustainable pulsed electron emission, which is justified by fluorescent image recording. The results imply the feasibility of self-powering field electron source by integrating highly efficient CNT cathode and high-voltage-output TENG. This paves the way to further realize the miniaturization, lightweight, safe, and cost-effectiveness of cold cathode-based vacuum electronic devices.