Direct growth of Au-Ga_2O_3 core-shell nanowires and their field emission properties

摘要

A simple, direct synthesis method for the growth of Au-Ga_2O_3 core-shell nanowires was reported in the work. The uneven concentration of precursor in Au catalyst in the vapor-liquid-solid process was proposed to induce a different growth rate at the interface between substrate and catalyst. The as-synthesized nanostructures were investigated by the use of transmission electron microscope. The existence of ～10 nm Ga_3O layer at the surface of Au tip was verified by high angle annular dark field images. The small electron affinity of the thin layer Ga_3O results in a remarkably high field enhancement factor of ～1200, and a lower turn-on field of ～4.7 V μm~(-1) in the field emission measurement. This simple approach and outstanding field emission performance promises future applications of core-shell nanowires in nanoelectronics and vacuum electronic.