Preparation of grass-like GaN nanostructures: Its PL and excellent field emission properties

We here report highly pure and single crystalline grass-like gallium nitride (GaN) nanostructures obtained on silicon substrate via catalyst-assisted CVD route under NH3 atmosphere inside horizontal tube furnace (HTF) by pre-treating the precursors with aqueous NH3. The as-obtained GaN nanostructures were characterized by XRD, SEM, EDS. HRTEM and SAED. The field emission (FE) characteristics of grass-like GaN nanostructures exhibited a turn-on field of 7.82 V mu m(-1) and a threshold field of 8.96 V mu m(-1) which are quite reasonable for applications in electron emission devices, field emission displays and vacuum microelectronic devices. Room temperature photoluminescence (PL) measurements of grass-like GaN nanostructures exhibited a strong near-band-edge emission at 368.8 nm (3.36 eV) without any defects related emissions which shows its potential applications in optoelectronics. (C) 2011 Elsevier B.V. All rights reserved.