Effect of thermal treatment on the aluminum hydroxide nanofibers synthesized by electrolysis of Al plates

Abstract

Nanofibrous aluminum hydroxides with high specific surface area have been synthesized by a novel process employing electrolysis of aluminum plates, which has the advantages of being very simple and fast. The structural phase transformation has been systemically investigated as a function of thermal treatment. Calcination of the as-prepared boehmite (AlO(OH)) powders produced a series of phase transition that finally transformed into the thermodynamically stable phase (alpha-Al(2)O(3)) at 1200 degrees C. After passing the transition region of about 350 degrees C, crystalline gamma-Al(2)O(3) phase gradually developed and above 400 degrees C, the boehmite was completely transformed into gamma-Al(2)O(3) phase. The produced gamma-Al(2)O(3) was clearly a nanofiber with a typical diameter of 2-5 nm and length of 20-50 nm. (C) 2011 Elsevier B.V. All rights reserved.\