铁氧簇合物的合成及其水解行为研究

水铁矿是广泛存在于地球表面的纳米水合铁氢氧化物。它不仅是生物体中铁卟啉的铁源，也是地下及地表水、工业及放射性污染物等的重要净化器。由于水铁矿的反应活性与其制备方法密切相关，因此，在分子水平上揭示水铁矿的形成机制对于理解其环境行为和优化其技术应用至关重要。申请课题中，申请人基于稀土离子亲氧性以及稀土离子配位水酸性明显低于三价铁离子配位水酸性之特点，拟采用稀土离子俘获铁氧簇合物。通过合成出不同核数、不同结构的稀土-铁氧簇合物，并研究这些不同核数、不同结构的稀土-铁氧簇合物水解行为，探讨水铁矿的形成机制；通过对不同稀土-铁氧簇合物水解形成的水铁矿对重金属或放射性离子吸附的效果研究，理解其环境行为和技术应用。因此，申请课题对于揭示水铁矿的形成机制，优化其技术应用具有重要意义。

Ferrihydrite is a nanoparticulate iron oxyhydroxide which is ubiquitous in the natural near-surface environment. It is not only present in the core of the protein ferritin, but also an important purifier for groundwater, industrial pollutants and radioactive elements. Owing to the reactivity of ferrihydrite closely related to its preparation, it is thus critical to have an understanding of ferrihydrite formation processes from solution at the molecular scale to underpin its environmental behavior and technological applications. In this proposal, we, based on the characteristic that lanthanide ions are oxyphilic and that their coordination water is less acidic than that of ferric ions, propose to capture discrete polynuclear iron-oxo clusters through lanthanide ions as stabilizers. We hope to explore the formation mechanism of the ferrihydrite by synthesizing a series of lanthanide-iron-oxo clusters with different nuclei and structures and studying their hydrolysis behavior, and to understand the environmental behavior and technological applications of the ferrihydrite by investigating the effect of the hydrolysis products of different lanthanide-iron-oxo clusters on the adsorption of heavy metal or radioactive ions. Thus, the proposal is helpful for to reveal the formation mechanism of the ferrihydrite and underpin its technological applications.