电化学控制离子分离(electrochemically controlled ion separation,ECIS)是一种环境友好的新型膜分离技术,通过电化学方法调节附着在导电基体上的离子交换膜的氧化还原电位来控制离子的置入与释放,从而使溶液中的金属离子得到分离并使膜得到再生。铁氰化镍(NiHCF)是一种结构类似分子筛的无机配位化合物,由于其对碱金属离子的选择性(Cs^+〉Rb^+〉K^+〉Na^+〉Li^+)不同可用于分离混合溶液中的碱金属离子,成为电控离子分离膜的首选材料。就ECIS过程机理、NiHCF薄膜的制备-结构-性能关系进行了总结并提出了一些新的研究方向。
Electrochemically Controlled Ion Separation (ECIS) is an environmentally benign way to separate ions via reversible electrochemical modulation of the matrix charge density. Ion loading and unloading can be easily controlled by modulating the redox states of ion exchange thin films prepared on conductive substrates, to perform the separation of ions from mixed solution and regeneration of the matrix. Nickel hexacyanoferrate (NiHCF), an inorganic coordination compound with an open, zeolite-like structure, is an excellent candidate for ECIS separation of alkali cations because of its different affinity for alkali cations (Cs^+〉Rb^+〉K^+〉Na^+〉Li^+). NiHCF can be made as electroactive thin film by electrochemical methods and capillary chemical deposition. The ECIS mechanisms, processing-structure-property relationship of the NiHCF thin film were reviewed and some research topics were recommended in this paper.