Enhanced ZnO Nanorods Field Emitter with Adsorbed Silver Nanoparticles

Abstract

Zinc oxide is low-cost and practical Ⅱ-Ⅵ chemical materials, which utilized to absorb silver nanoparticle on zinc oxide. It can improve the electrical characteristics of the zinc oxide. In this study, ZnO nanorods were prepared via hydrothermal method and use silver nitrate solution to absorb silver nanoparticle on ZnO nanorods. Finally, surface morphology observation by SEM, crystal (XRD), optical properties (PL) , element content (EDS),(TEM) and measurement field emission were measured. The results indicate that ZnO nanorods which have an average diameter and maximum length of around 35nm~75nm and 2.14um, respectively. It was found that the silver nanoparticle on ZnO nanorods, and silver nanoparticle have an average diameter of around 18nm~95nm. The existence of Ag was examined by energy diffraction spectra (EDS). The structural characteristics of the ZnO were measured by X-ray diffraction (XRD). It was found that the peaks related to the wurtzite structure ZnO (002), (102), (103), and (112) diffraction peaks, the (002) peak indicates that the nanorods were preferentially oriented in the c-axis direction. The PL spectra of all the samples were shown in two emission bands, ultraviolet (UV) and visible (blue and green) bands, were observed in each spectrum. The UV emission is always ascribed to the band gap of ZnO, and the strong visible emission centered at around 500 nm is assigned to the defects (such as oxygen vacancies and interstitial zinc) in ZnO. It was also found that the turn-on electrical field reduced from 3.2 to 2.5 V/μm and the field enhancement factor enhanced from 748 to 2007.