基于石墨烯及其复合物电极的电容去离子技术研究进展

电容去离子技术是一种高效节能、绿色环保的脱盐方法, 通过施加静电场, 强制离子向两侧电极迁移, 使其被电极表面产生的双电层吸附, 从而达到脱盐的目的。电容去离子技术的关键是高性能电极材料的制备, 要求具有较高的比表面积、合理的孔径分布和良好的导电性。石墨烯具有较高的理论比表面积和优异的导电性, 是一种理想的电极材料。然而由于石墨烯的聚集效应, 实际比表面积远远低于理论值, 将石墨烯制备成三维网络结构或将石墨烯与其他材料进行复合可以克服聚集效应, 提高电极的脱盐性能。本文综述了基于石墨烯及其复合物电极的电容去离子技术研究进展、存在的问题及应用前景。

Research Progress of Graphene and Its Composites as Electrodes for Capacitive Deionization

Capacitive deionization is an energy-efficient and environment-friendly desalination method, which forces ionic species toward oppositely charged high-surface-area electrodes under an electric field to achieve the purpose of desalination. The key technology is to prepare electrode materials, which require high specific surface area, reasonable pore size distribution and excellent electrical conductivity. Graphene is a desired kind of electrode material used in capacitive deionization for its high specific surface area and wonderful conductivity. However, the actual specific surface area is far below the theoretical value due to the effect of aggregation of graphene. The three-dimensional graphene or the composite materials can overcome aggregation effect to improve the performance of electrode. The research progress of the capacitive deionization technology based on graphene and its composite electrode are reviewed in detail. The existing problems and application prospect are also objectively pointed out in this review.