Effect of variation of molar ratio (pH) on the crystallization of iron oxide phases in microwave hydrothermal synthesis
Metadata of CSIR Papers
View Archive Info| Field | Value | |
| Title |
Effect of variation of molar ratio (pH) on the crystallization of iron oxide phases in microwave hydrothermal synthesis
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| Creator |
Dhage, SR
Khollam, YB Potdar, HS Deshpande, SB Bakare, PP Sainkar, SR Date, SK |
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| Subject |
Materials Science, Multidisciplinary; Physics, Applied
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| Description |
Microwave hydrothermal (MH) route was employed to synthesize various phases of iron oxide powders by using ferrous sulphate and sodium hydroxide as starting chemicals. All the MH reactions were carried out under the identical MH conditions of 190 degreesC, 154 psi, 30 min by varying molar ratio (MR) of FeSO4/NaOH (i.e. pH variation) from 0.133 to 4.000 in the solution. It was found that the variation of MR of FeSO4/NaOH has a profound effect on the crystallization of various phases of iron oxides under identical MH processing conditions. The stoichiometric, submicron-sized (0.15 - 0.2 mum), spherical agglomerates of Fe3O4 powders were obtained if MR of FeSO4/NaOH equal to 0.133 (pHgreater than or equal to10) was maintained. On the other hand, non-stoichiometric Fe3O4 powders were obtained for all the higher MR of FeSO4/NaOH between 0. 133 and 4.00 (6.6<pH<10). However, when MR of FeSO4/NaOH was equal to 4.00 (pH approximate to 6.6), a varied distribution of shapes and sizes (1 - 5 mum) of agglomerates of alpha-Fe2O3 powders were produced. Various analytical tools such as XRD, Mossbauer spectroscopy, scanning electron microscopy (SEM) and EDAX were used to characterize the MH-derived powders. (C) 2002 Elsevier Science B.V. All rights reserved.
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| Publisher |
ELSEVIER SCIENCE BVAMSTERDAMPO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS
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| Date |
2011-09-24T09:59:16Z
2011-09-24T09:59:16Z 2002 |
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| Type |
Article
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| Identifier |
MATERIALS LETTERS
0167-577X http://hdl.handle.net/123456789/24222 |
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| Language |
English
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