Abstract
Mixed metal oxides consisting of Zn and Fe were prepared by calcining ZnFe-mixed metal hydroxide at respective temperature of 400, 500 and 600 °C. According to X-ray diffraction, the calcination resulted in the evolution of wurtzite ZnO partially with ZnFe2O4 spinel at high temperature. The local structure around Fe and Zn measured by X-ray absorption spectroscopy did not show difference upon temperature, suggesting the intimate association between zinc oxide and iron oxide. The magnetic property of mixed metal oxide was paramagnetic for calcination temperature of 400 and 500 °C; whereas superparamagnetism was observed in 600 °C calcined sample. The specific surface area and pore volume was the highest for mixed metal oxide calcined at 500 °C showing 66.4 m2/g and 0.908 cm3/g, respectively. Temperature programmed desorption of ammonia revealed that the ZnFe-mixed metal oxide had majorly strong Lewis acid site compared with previously reported ZnOs. The acid strength was proportional to the calcination temperature, and however, total acidity decreased for 600 °C calcined oxide. Taking into account the phase, porosity and acidity, the ZnFe-mixed metal oxide prepared at 500 °C could be the most advantageous as acid catalysts.
Original language | English |
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Pages (from-to) | 454-458 |
Number of pages | 5 |
Journal | Journal of Solid State Chemistry |
Volume | 269 |
DOIs | |
State | Published - Jan 2019 |
Keywords
- Calcination
- Mixed metal oxides
- Phase
- Porosity
- Temperature programmed desorption