基于可变价NiFe-LDH/rGO对磷酸根离子的特异性电控分离

磷是一种不可再生资源。为解决现有磷污染以及磷资源流失等问题，通过油浴与热化学还原相结合的方法，成功制备出一种NiFe-LDH/rGO电活性杂化膜材料。使用电化学方法，在氧化还原电位的控制下，Ni、Fe(Ⅱ/Ⅲ)双金属发生核外电子的跃迁，高价态的Ni、Fe(Ⅲ)与\mathrm{P}{\mathrm{O}}_{\mathrm{4}}^{\mathrm{3}-}发生内球络合作用，实现\mathrm{P}{\mathrm{O}}_{\mathrm{4}}^{\mathrm{3}-}的选择性置入-置出。实验获得270 mg·g^-1的高\mathrm{P}{\mathrm{O}}_{\mathrm{4}}^{\mathrm{3}-}吸附容量及85%以上的再生效率。此外，该杂化膜材料在共存离子存在的复杂水体中，对\mathrm{P}{\mathrm{O}}_{\mathrm{4}}^{\mathrm{3}-}具有优异的选择性，为磷石膏渗滤液以及各种含磷废水污染等问题的解决提供有效的理论技术支撑，具有广阔的应用前景。

Specific electronically controlled separation of phosphate anions based on variable valence NiFe-LDH/rGO

Phosphorus is a non-renewable resource. In order to solve the problems of existing phosphorus pollution and phosphorus resource loss, a NiFe-LDH/rGO electroactive hybrid film material was successfully prepared in this study by a combination of oil bath and thermochemical reduction. An ESIX process allows the NiFe-LDH/rGO hybrid film achieving a controllably selective uptake and release of the phosphate anions. This route involves tuning potential steps to regulate the redox states of the composite film and the variable metal (e.g., Ni, Fe (Ⅱ)/(Ⅲ)) in coordination centers, as the inner-sphere complexation of the metals to phosphate anions is combined with the assistance of the outer electric field. A high absorption capacity (270 mg·g^-1) and regeneration rate (>85%) were achieved, together with good cycle stability. This route provides an efficient, theoretical and technical support to solve the problems phosphogypsum leachate and various phosphorus wastewater pollution, which presents a broad application prospect.