Field Emission of Electrons Powered by a Triboelectric Nanogenerator

Field emission of electrons usually requires high voltage (HV) of at least 100 V, which limits its applications due to the high cost, instability, portability issues, etc., of the HV instrument. Triboelectric nanogenerators (TENGs) have been developed to provide an HV of at least several kV for portable/mobile instrument, with controllability already demonstrated. Here, the field emission of electrons driven by TENG, namely, tribo-field emission, is presented for the first time. The emission voltage and the charge transfer per cycle can be tuned and controlled by TENG. The current peak generated from TENG with limited charge transfer is demonstrated to be more favorable than the direct current HV source in terms of emitter protection. A unidirectional continuous emission current is achieved through the tribo-field emission. A cathode-ray tube can be powered by TENG, with hours of illumination demonstrated through only one sliding motion. Such approach can provide a potential solution for controllable, stable, and portable field-emission devices without any additional external power sources.