Morphology, Microstructure, and Magnetic Properties of Ordered Large-Pore Mesoporous Cadmium Ferrite Thin Film Spin Glasses

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• 作者：Christian Reitz ; Christian Suchomski ; Venkata Sai Kiran Chakravadhanula ; Igor Djerdj ; Zvonko Jagli膷i膰 ; Torsten Brezesinski
• 刊名：Inorganic Chemistry
• 出版年：2013
• 出版时间：April 1, 2013
• 年：2013
• 卷：52
• 期：7
• 页码：3744-3754
• 全文大小：684K
• 年卷期：v.52,no.7(April 1, 2013)
• ISSN：1520-510X

文摘

Herein, we report the synthesis, microstructure, and magnetic properties of cadmium ferrite (CdFe₂O₄) thin films with both an ordered cubic network of 18 nm diameter pores and single-phase spinel grains averaging 13 nm in diameter. These mesoporous materials were produced through facile polymer templating of hydrated nitrate salt precursors. Both the morphology and the microstructure, including cation site occupancy and electronic bonding configuration, were analyzed in detail by electron microscopy, grazing incidence small-angle X-ray scattering, Raman and X-ray photoelectron spectroscopy, and N₂-physisorption. The obtained data demonstrate that the network of pores is retained up to annealing temperatures as high as 650 掳C鈥攖he onset of crystallization is at 蠎 = (590 卤 10) 掳C. Furthermore, they show that the polymer-templated samples exhibit a 鈥減artially鈥?inverted spinel structure with inversion parameter 位 = 0.40 卤 0.02. This differs from microcrystalline CdFe₂O₄ which shows virtually no inversion. Magnetic susceptibility studies reveal ferrimagnetic spin coupling below 147 K and further point to the likelihood of glassy behavior at low temperature (T_f 鈮?60 K). In addition, analysis of room temperature magnetization data indicates the presence of sub-10 nm diameter superparamagnetic clusters in an otherwise paramagnetic environment.