面向重金属离子检测的金属有机框架-石墨烯气凝胶复合敏感电极的构筑与性能研究

重金属污染直接危害到人类的健康与生命。电化学传感器有望实现现场重金属离子的快速检测，但仍然需要解决电极材料灵敏度低、一致性差和成本高的问题。在前期纳米材料和石墨烯材料电化学特性深入研究的基础上，本项目提出基于贵金属修饰的双金属有机框架(MOF)–石墨烯(rGO)气凝胶复合敏感电极，利用ZnCo-MOF核壳结构大孔隙率、高比表面积和rGO良好的导电性的特点，结合贵金属修饰的协同效应，形成稳定的电化学特能，提升电催化过程中氧化-还原反应的电子转移速率、反应动力学和反应催化活性，有望大幅度提升重金属离子电化学传感检测的灵敏度。同时设计开发基于气凝胶前驱体（水凝胶）的静电喷墨打印图形化批量加工工艺，研制出检测限低于国家《生活饮用水卫生标准》所规定重金属指标限值的、高灵敏的、批量化一致性好的、适用于现场作业的电化学传感器，实现对于痕量重金属离子的现场检测，对环境安全与污染治理有重要的推动作用。

Heavy metal contamination is a threat to human health and life. Electrochemical sensors are expected for the on-site fast detection of heavy metal ions, however several problems of the electrodes, including low sensitivity, bad consistency and high cost, are required to solve. Based on the previous in-depth investigation of electrochemical characteristics of graphene and other nanomaterials, bimetal organic frame (MOF) – reduced graphene oxide (rGO) aerogel sensitive composite electrodes modified by noble metals are proposed. ZnCo-MOF core-shell structure is of high porosity and high specific surface area and rGO has good conductivity. Together with the synergetic effect of the noble metal particles, the electron transfer and reaction kinetics can be promoted by the stable electrochemical properties of the electrodes. These will render high sensitivity in the electrochemical detection of heavy metal ions. Meantime, the electrostatic ink-jet printing technique based on aerogel precursor (hydrogel) for graphic batch fabrication processes is designed. Based on the above proposed scheme, the electrochemical sensors with low detection limit, high sensitivity, good consistency and low cost are expected to be developed for heavy metal ions detection. The detection limit of the fabricated sensors is anticipated to be lower than the value set by the national standard "drinking water hygiene standards". The implementation of the project will actively promote the environmental safety and pollution control.