Field-emission properties of the platinum coated SiO2 nanowires synthesized by thermal evaporation method

Silicon oxide (SiO2) nanowires were synthesized on a 3 cm × 3 cm Si wafer by thermal evaporation of Si@SiO2 core–shell particles under argon atmosphere at 1000 °C for 1 h. The SiO2 nanowires were of diameters ranging from 30 to 100 nm and the lengths were of several micrometres. The growth mechanism of SiO2 nanowires was studied and suggested to be a vapour–solid mechanism. Field-emission (FE) properties of the Pt coated SiO2 nanowires were studied and the result showed that a turn-on electric field of 2.9 V µm−1 was obtained at the vacuum gap of 200 µm. Good FE properties of the Pt coated SiO2 nanowires resulted from the high aspect ratio of the SiO2 nanowires and the excellent work function of platinum.