Kinetic Synthesis of Nanomaghemite Mediated by Arsenate
Kinetic Synthesis of Nanomaghemite Mediated by Arsenate
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砷酸盐介导的纳米磁赤铁矿的动力学合成
DOI：
10.1166/jnn.2017.14528
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发表时间：
2017-09
影响因子：
--
通讯作者：
Chen Tianhu
中科院分区：
文献类型：
--
作者：
Zhou Yuefei;Yin Jiaojun;Xie Qiaoqin;Yue Zhengbo;Wei Lin;Chen Tianhu
氢氧化铁中元素的形成、转化和行为是复杂的。在这项研究中，我们开发了一种微量滴定法来控制生长动力学和铁（羟基）氧化物的转化。在所有条件下，水铁矿是主要的相和次要的相控制的合成速率和砷酸盐添加。在没有As的实验中，在高滴定速率下形成纳米磁赤铁矿，而在低速率下形成针铁矿和赤铁矿。在As/Fe = 0.1的实验中，在所有条件下形成纳米磁赤铁矿，并且纳米磁赤铁矿颗粒的尺寸随着滴定速率的降低而增加。结果表明，纳米磁赤铁矿是水铁矿沉淀过程中的常见相，但由于其高度不稳定性而难以检测。与纳米磁赤铁矿相容的阴离子，如磷酸盐和砷酸盐，可以增加其稳定性。我们的研究对土壤磁性和工业材料设计具有重要意义。
The formation, transformation, and behavior of elements are complex for Fe (oxyhydr)oxides. In this study, we developed a micro-titration method to control the growth kinetics and transformation of Fe (oxyhydr)oxides. Under all conditions, ferrihydrite was the main phase and the minor phases were controlled by the synthesis rate and arsenate addition. In experiments without As, nanomaghemite was formed at high titration rates, while goethite and hematite were formed at low rates. In experiments at As/Fe = 0.1, nanomaghemite was formed under all conditions and the size of the nanomaghemite particles increased as the titration rate decreased. The results indicate that nanomaghemite is a common phase in the precipitation of ferrihydrite, although it is difficult to detect because of its high instability. Anions that are compatible with nanomaghemite, such as phosphate and arsenate, can increase its stability. Our study has important implications for soil magnetism and industrial material design.