薄膜扩散梯度（DGT）技术是对水体中痕量重金属离子进行原位监测的有效手段。然而，常规DGT中的捕收层是将吸附材料嵌入水凝胶中制得。不仅水凝胶会影响其对重金属离子的选择性吸附，而且吸附材料的嵌入往往会导致成凝胶性能下降而难以成胶。为此，项目采用静电纺丝技术可控构筑聚合物螯合纤维膜（如PAN, PVA等）直接用作DGT捕收层，从而选择性富集重金属离子，达到对痕量重金属离子的原位、准确监测。通过电纺参数调控以及低温等离子体表面修饰功能基团（如-NH2,-SH等），实现选择性吸附。通过多组分竞争吸附动力学、平衡吸附等温线及Monte Carlo 分子动力学模拟吸附类型，揭示选择性吸附微观过程；利用XPS、EXAFS 等分析手段研究重金属离子与纤维膜的作用机理，揭示螯合纤维膜选择性吸附的构效关系和DGT监测机制。项目不仅为DGT提供了简便的捕收层，也为螯合纤维膜的电纺制备及其吸附性能调控提供参考。

Diffusive gradients in thin films (DGT) technology is an effective method for in-situ measurement of trace heavy metals ions in waters. However, traditional binding layer in DGT device is made by incorporation of adsorbent into gel. The gel not only would decrease the selective adsorption capacity of adsorbent towards heavy metal ions but also the incorporation of adsorbent sometimes results in difficulty in gel formation. To solve this problem, this proposal utilize electrospinning technology to fabricate polymer chelate fiber membranes (for example PAN, PVA, etc) for application as binding layer in DGT devices directly, to selective adsorb target heavy metal ions and subsequently in-situ accurate measurement of trace heavy metal ions by DGT devices. Adjust electrospinning parameters and supply selective groups (such as -NH2, -SH, etc.) on the fiber membranes by low temperature plasma to achieve selective adsorption. To investigate adsorption process by kinetic and equilibrium multi-component adsorption experiments and simulation of adsorption model on the basis of Monte Carlo kinetic molecular simulation. To reveal the adsorption mechanism between polymer fiber membranes and heavy metal ions by spectra of XPS、EXAFS, etc, leading to investigation on relationship between structure of chelate fiber membranes and selective adsorption performance and further mechanism of selective in-situ measurement of DGT. This proposal not only supplies facile binding layer for DGT devices but also provides useful data for electrospinning preparation of polymer chelate fiber membranes and their adsorption properties control.