Hydrothermal Synthesis of Ammonium Aluminum Carbonate Hydroxide (AACH) Nanoplatelets and Nanofibers pH-Controlled Morphologies

Abstract

Abstract-NH 4 Al(OH) 2 CO 3 precursors were prepared using Al(NO 3 ) 3 and NH 4 HCO 3 as raw materials. The structural, morphological, and porous properties of the materials were investigated by BET, X-ray Diffraction (XRD), and Scanning Electron Microscope (SEM).The morphology and aspect ratios of resulting AACH nanoparticles were significantly influenced by the pH values in the preparation of solid precipitates.There were two kinds of morphology present, nanofibers and nanoplates. After thermal treatment at 550 o C in air for 4 hours, the morphologies of the nanostructures werewell preserved while the crystal structure was converted to γ-alumina.