Morphology Evolution in Hydrothermal Synthesis of Mesoporous Alumina

Boehmite with varied morphologies was successfully synthesized from aluminum ammonium sulfate hydrate and urea, as well as poly-glycol-2000 by hydrothermal method.The experimental results show that boehmite microspheres, microfibers and 3D hierarchical structured AlOOH can be fabricated only by adjusting hydrothermal temperature.SEM images indicate that boehmite decomposes into γ-Al 2 O 3 phase after heat-treatment through a topotactical process.TEM studies present that the mesopores are formed in γ-Al 2 O 3 particles.Based on these investigations, a temperature-dependent morphology formation mechanism is proposed.Besides, the as-synthesized alumina excited at 325 nm shows emission in the range of 380 nm to 500 nm, centered at 409 nm and 467 nm.