Calcination products of gibbsite studied by X-ray diffraction, XPS and solid-state NMR

被引：61

作者：

Malki, A. ^{[1
]}

Mekhalif, Z. ^{[2
]}

Detriche, S. ^{[2
]}

Fonder, G. ^{[2
]}

Bournaza, A. ^{[1
]}

Djelloul, A. ^{[1
]}

机构：

[1] Univ Abbes Laghrour, Fac Sci & Technol, Lab Struct Proprietes & Interact Inter Atom LASPI, Khenchela 40000, Algeria

[2] Fac Univ Notre Dame Paix, Lab Chim & Electrochim Surfaces, B-5000 Namur, Belgium

来源：

JOURNAL OF SOLID STATE CHEMISTRY | 2014年 / 215卷

关键词：

Gibbsite; Transition alumina; X-ray diffraction; X-ray photoelectron microscopy; Al-27 nuclear magnetic resonance; ALUMINUM; TRANSFORMATION; GAMMA; CHI;

D O I：

10.1016/j.jssc.2014.03.019

中图分类号：

O61 [无机化学];

学科分类号：

070301 ; 081704 ;

摘要：

The changes caused by heat treatment of gibbsite powder at 300-1473 K were studied using the X-ray diffraction (XRD), X-ray photoemission (XPS) spectra and Al-27 magic angle spinning nuclear magnetic resonance spectroscopy (Al-27 MAS NMR). XRD analysis indicates that the transformation sequence involves the formation of kappa-Al2O3 as an intermediate phase between chi- and alpha-Al2O3. The crystallite size of chi-Al2O3 is as small as 10 nm. XPS analysis indicates that the ratio of aluminium atoms to oxygen atoms in chi-Al2O3 and kappa-Al2O3 increases, whereas the expected ratio is observed in alpha-Al2O3. The percentage of AlO4 units in the transition aluminas follows the same behaviour as the ratio of Al/O. (C) 2014 Elsevier Inc. All rights reserved.

引用

页码：8 / 15

页数：8

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