Shape and Doping Enhanced Field Emission Properties of Quasialigned 3C-SiC Nanowires

We have reported the enhanced field emission properties of quasialigned 3C-SiC nanowires synthesized via catalyst assisted pyrolysis of polysilazane. The as-synthesized Al-doped SiC nanowires possess a tapered and bamboo-like structure with clear and tiny tips sized in several to tens of nanometers. The fabricated SiC nanowires have extremely low turn-on fields of 0.55-1.54 V mu m(-1) with an average of similar to 1 V, mu m(-1), which is the lowest one ever reported for any type of SiC emitters. The field-enhancement factor has been calculated to be 2983. The superior FE properties can be clearly attributed to the significant enhancements of the tapered and bamboo-like unique morphology and Al doping of SiC nanowires. Density functional theory calculations suggest that Al dopants in 3C-SiC nanowires could favor a more localized state near the Fermi energy, which improves the electron field emissions. We strongly believe that the present work will open a new insight in the fabrication of field emission sources with ultralow turn-on fields enhanced by both shape and doping.