Enhanced field emission from ZnO nanorods via thermal annealing in oxygen

Abstract

To optimize the field emission behavior of the ZnO nanorods, postthermal annealing in different ambience was conducted. The field emission properties of the ZnO nanorods are considerably improved after annealing in oxygen and getting worse when annealing in air or ammonia. Photoluminescence and Raman spectroscopy were employed to elucidate the reason for such a significant improvement of the field emission when annealing in oxygen. Those detailed analyses suggested that oxygen annealing can reduce the oxygen vacancy concentration, improve the crystal quality, lower the work function, and increase the conductivity of the ZnO nanorods. Our work is important for applications of ZnO nanorods as a promising candidate in flat panel displays and high brightness electron sources.

Soft template synthesis of ZnO nanorods and their optical properties

“…There are many reasons for variation of the strength and location of UV peaks. In the present study, we believe it may be due to electron-phonon interaction at different temperatures [6,9,10]. With increasing temperature, the electron-phonon interaction becomes stronger.…”

Strategies to Improve Field Emission Performance of Nanostructural ZnO

“…Various factors, such as good contact between the substrate and the nanostructures, good crystal quality, thermal and chemical stability, structural rigidity, and uniform height determine a stable emission current. 7,8 Figure 6 shows the variation of the emission current density of ZnO nanotubes (Fig. 2d) as a function of time.…”

“…7 In fact, there are some reports on FE from nanostructural ZnO. [8][9][10][11] Some researchers even coated ZnO nanoparticles on the CNT surface to improve the FE performance. 12,13 Although many valuable results have been reported, the general methodologies of realizing an effective ZnO field emitter have not been revealed.…”

Enhanced field emission from ZnO nanowire arrays utilizing MgO buffer between seed layer and silicon substrate

“…The Fowler-Nordheim (FN) plots in the inset of Fig. 5 shows a roughly linear relationship for nanowire arrays with MgO layer, implying that a quantum tunneling mechanism is responsible for the emission [33]. For the FN emission,…”