Synthesis and Field Emission Properties of Helical GaN Nanowires

Helical gallium nitride nanowires were synthesized by chemical vapor deposition using a Pt catalyst. The prepared helical GaN nanowires with a single-crystalline hexagonal wurtzite structure have a coil diameter of 150–280 nm and lengths of up to tens of micrometers. The helical GaN nanowires have six equivalent 〈0 $ \bar{1} $ 11〉 growth directions along the 0001] axis. Field emission measurements show that helical GaN nanowire sheets possess excellent field emission properties, with a low turn-on field of ~4.5 V/μm and a high field enhancement factor of ~2,751. It is believed that this material’s excellent electron emission behavior can be attributed to its unique three-dimensional spiral structure. The growth mechanism of helical GaN nanowires has also been analyzed.