The information on the variations of indium composition, aggregation size, and quantum-well width is crucially important for understanding the optical properties and, hence, fabricating efficient light-emitting devices. Our results showed that spinodal decomposition could occur in InGaN/GaN multiple quantum wells with indium content in the range of 15%-25% ͑grown with metal-organic chemical-vapor deposition͒. A lower nominal indium content led to a better confinement of indium-rich clusters within InGaN quantum wells. The InGaN/GaN interfaces became more diffusive, and indium-rich aggregates extended into GaN barriers with increasing indium content. It was also observed that indium-rich precipitates with diameter ranging from 5 to 12 nm preferred aggregating near V-shaped defects.
We report the first synthesis of titanium nitride (TiN) nanoparticles inside the nanoscale channels of mesoporous silica SBA-15. The TiN precursor, Ti(NMe 2 ) 4 in toluene, was incorporated into the methyl group-modified channels of the SBA-15 powder. The functionalization of pore surfaces with methyl groups generates hydrophobic surfaces that facilitate impregnation with Ti(NMe 2 ) 4 and minimizes reactions between the TiN precursor and the hydroxyl groups on the surface of SBA-15. Formation of TiN nanoparticles inside the mesoporous channels of SBA-15 was carried out by subsequent ammonolysis at high temperatures (700-750°C). The final products have been characterized by TEM and EELS images, powder XRD patterns, FTIR spectra, UV-vis absorption spectra, and nitrogen adsorption isotherm measurements to confirm the presence and distribution of TiN nanoparticles in the SBA-15 samples.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.