Room-temperature synthesis of GaN nanopowder

The synthesis of GaN by combining Li 3N and GaCl 3 in a 1:1 mixture of benzene and ether or in pure ether was investigated. Powder X-ray diffraction measurements on the unannealed powders revealed two broad peaks centered at 35 and 62°. Raman spectra of the GaN powders were collected using nonresonance excitation at 532 nm and the annealed samples were readily identified as GaN from their XRD patterns. High-resolution transmission electron microscopy (HR-TEM) images of the sample annealed at 310°C revealed nanosized crystals of differing phases averaging approximately 10 nm in diameter. Wurtzite and zinc blend crystals were easily identified by measurement of (100) and (200) plane spacings. A strong electronic quantum confinement in the as-prepared particles was observed as no surface capping ligand was added to restrict particle growth.