عنوان مقاله [English]
Nowadays, electron sources based on field emitters have an important role in our life. For example, utilizing the field emitters in electron microscopes, field emission displays, and solar cells are the main application of the field emission. In recent years carbon naotubes (CNTs) have been considered as a good electron emitter because of their unique electron conductivity. Also, TiO2 nanotubes as a metal oxide semiconductor with capability to grow on a conductive substrate can be a promising candidate for electron emitter. In this study, we have focused on investigating the field emission characteristics of the bare TiO2 nanotubes and CNT coated TiO2 nanotubes to achieve a high current electron emitter. In this study, we have shown that the layered nanostructures have a significantly higher electron emission comparing to the bare TiO2 nanotubes. Also, the emission current from these nanostructures changes udder the light exposure.
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