PEG-directed hydrothermal synthesis of alumina nanorods with mesoporous structure via AACH nanorod precursors

Al2O3 nanorods with mesoporous structures are successfully synthesized from a hydrothermal and thermal decomposition process via the ammonium aluminum carbonate hydroxide (denoted as AACH) precursors. TEM images show that the average diameter of Al2O3 nanorods is about 60 nm, and the length is around 1–2 μm. The experimental results show that well-crystallized mesopores with hierarchically distributed pore sizes are embedded in the Al2O3 nanorods. The N2 adsorption–desorption experiment indicates that the as-synthesized alumina nanorods have large surface area (ca. 176 m2/g) and narrow pore-size distributions. At the same time, the as-prepared Al2O3 nanorods exhibit strong photoluminescent properties at room temperature. A plausible surfactant-induced nanorod formation mechanism using the poly ethylene glycols as the template agent for the nanorod assembly is also proposed.