Synthesis of single-crystalline α-Si3N4 nanobelts by extended vapour–liquid–solid growth

Abstract

A simple chemical method for the production of single-crystallineα-Si3N4 nanobelts has been developed, consisting of nitridation of a high-Si-content Fe–Si ‘catalyst’ by ammoniaat 1300 °C. The as-synthesized product was characterized by means of x-ray diffraction,electron microscopy and energy-dispersive x-ray spectroscopy. Theα-Si3N4 nanobelts have widths of 60–120 nm, thicknesses of 10–30 nm and lengths up to microns.Four intense green–blue luminescence bands at 398 nm (3.12 eV), 434 nm (2.86 eV), 492 nm(2.52 eV) and 540 nm (2.30 eV) were observed and analysed for the product, which indicatesthe potential applications in optoelectronics. The growth mechanism has also beenspeculated upon. The potential technological importance of the product, the simplicity ofthe preparation procedure, as well as the cheap commercial precursor of Fe–Sialloy particles makes this study both scientifically and technologically interesting.