Low temperature synthesis of nano alpha-alumina powder by two-step hydrolysis. (January 2016)

• Record Type: Journal Article
• Authors: yan, Ting; Guo, Xiaode; Zhang, Xiang; Wang, Zhixiang; Shi, Jinqiu
• Is Part Of: Materials research bulletin. Volume 73(2016)
• Page Start: 21
• Page End: 28
• Publication Date: 2016-01
• Subjects: A. Nanostructures -- A. Oxide -- B. Chemical synthesis -- B. Phase transitions -- C. X-ray diffraction; Materials -- Periodicals; Crystal growth -- Periodicals; Matériaux -- Périodiques; Cristaux -- Croissance -- Périodiques; Crystal growth; Materials; Periodicals; 620.11
• DOI: 10.1016/j.materresbull.2015.08.021
• Languages: English
• ISSNs: 0025-5408

Abstract

Graphical abstract: Highlights: The nano α-Al2 O3 with good dispersion was prepared by two-step hydrolysis. α-Al2 O3 powders were added as seed particles in the hydrolysis. This article indicated that the glucose could impel the γ-Al2 O3 transformed to α-Al2 O3 directly. This article indicated that the addictive of α-Al2 O3 seed could improve the phase transformation rate of γ-Al2 O3 to α-Al2 O3 . In this article, the pure α-Al2 O3 could be obtained by calcining at 1000 °C for 1.5 h. Abstract: The ultral fine alpha-alumina powder has been successfully synthesized via two-step hydrolysis of aluminum isopropoxide. Glucose and polyvinyl pyrrolidone were used as surfactants during the appropriate processing step. The alpha-alumina powder was used as seed particles. Several synthesis parameters, such as the amount of seeds, surfactants, and calcination temperature, were studied by X-ray diffraction (XRD), Fourier transform infrared spectra (FTIR), Thermogravimetry-differential scanning calorimetry (TG-DSC), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The experimental results showed that glucose greatly lower the phase transformation temperature of alpha-alumina by impelling the gamma-alumina transformed to alpha-alumina directly, and the seed could improve the phase transformation rate of alpha-alumina, the polyvinylpyrrolidone have an effect on preventing excessive grain growth and agglomeration of alpha-alumina powder. Comparatively well dispersed alpha-alumina powder with particle size less than 50 nm can be synthesized through this method after calcinations at 1000 °C for 2 h.