Abstract The synthesis and characterization of magnesium ferrite MgFe 2 O 4 prepared by co-precipitation and sol gel combustion is reported. Structural characterization showed that all the samples have single spinel phase. The co-precipitated sample exhibits smaller grains and twice higher BET surface than the sol gel combustion samples. The powder was shaped to dedicated chemo-resistive home-made sensors devices. The electrical properties and sensing properties towards carbon dioxide of both MgFe 2 O 4 powders were studied. The type of charge carriers were analysed on the basis of the change in resistance in the presence of air and argon. The sensing response towards CO 2 was found to be dependent on the morphology of the powder sample and the CO 2 concentration. A high response of 36% towards 5000 ppm of CO 2 was reached which is good for this gas. The key role of the Mg ions modulating the electrical properties is discussed.

中文翻译：

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合成方法和形貌对镁铁氧体MgFe 2 O 4 增强CO 2 传感性能的影响

摘要 报道了共沉淀法和溶胶凝胶燃烧法制备铁酸镁MgFe 2 O 4 的合成和表征。结构表征表明所有样品都具有单尖晶石相。与溶胶凝胶燃烧样品相比，共沉淀样品的颗粒更小，BET 表面积高两倍。粉末被塑造成专用的化学电阻自制传感器设备。研究了两种MgFe 2 O 4 粉末对二氧化碳的电学性质和传感性质。根据在空气和氩气存在下电阻的变化来分析电荷载流子的类型。发现对 CO 2 的传感响应取决于粉末样品的形态和 CO 2 浓度。对 5000 ppm 的 CO 2 达到了 36% 的高响应，这对这种气体有利。讨论了镁离子调节电性能的关键作用。