Influence of annealing temperature on the phase transformation of Al2O3

• Main Authors: Anggono T. (Author), Birowosuto M.D (Author), Febriani F. (Author), Herbani Y. (Author), Isnaeni (Author), Izzuddin H. (Author), Kamarulzaman, N. (Author), Mahat, A.M (Author), Mastuli, M.S (Author), Oemry F. (Author), Rusydi A. (Author), Sudiro T. (Author), Wicaksono D.H.B (Author)
• Format: Article
• Language: English
• Published: American Institute of Physics Inc. 2016
• Online Access: View Fulltext in Publisher; View in Scopus
• ISBN: 0094243X (ISSN); 9780735413580 (ISBN)
• DOI: 10.1063/1.4941627

In the present study, Al2O3 powders were prepared via a self-propagating combustion method using citric acid as a combustion agent. Effects of annealing temperature on the phase transformation of the prepared powders were studied on samples annealed at 800 °C and 1000 °C. The Al2O3 samples were characterized using X-Ray diffraction (XRD), field emission scanning electron microscopy (FESEM) and N2 adsorption-desorption measurements. The XRD results showed that pure η-phase and pure α-phase of Al2O3 were obtained at 800 °C and 1000 °C, respectively. Their crystallite sizes are totally different as can be seen clearly from the FESEM micrographs. The η-Al2O3 sample annealed at low temperature has crystallite size smaller than 10 nm compared to the α-Al2O3 sample annealed at higher temperature which has crystallites from few microns to hundreds microns in size. From the BET (Brunauer-Emmett-Teller) method, the specific surface area for both samples are 59.4 m2g-1 and 3.1 m2g-1, respectively. It is proposed that the annealing temperature less pronounced for the morphology, but, it is significant for the phase transitions as well as the size and the specific surface area of the Al2O3 samples. © 2016 AIP Publishing LLC.