摘要
为制备可靠、精确的分子筛氧化石墨烯(GO)膜,克服基于厚度调控的抽滤自组装GO膜分离性能提升和通量减小之间的矛盾关系,采用界面自组装法,制备了具有更加紧密层间结构的GO膜,并对其性能进行了表征。实验结果表明:与抽滤自组装法制备GO膜相比,界面自组装法可以实现更加紧密的层间结构;在化学环境相似的条件下,界面自组装膜的层间距可达0.75 nm,较抽滤自组装膜减小了0.10 nm左右;成膜机理和速率是GO膜层间结构的主要影响因素。将该膜用于金属离子水溶液的截留实验,结果表明:界面自组装GO膜对Mg~(2+)的截留率可达70%左右,是抽滤自组装膜的1.3倍。
To prepare reliable and accurate graphene oxide(GO) membrane for molecular sieving, the interface self-assembly method is adopted to prepare GO membranes with more compact interlayer structure. This method can solve the problem that the contradictory relationship between the separation performance and flux caused by thickness control when tuning the performance of GO membrane. The experimental results showed that the interface self-assembly method can achieve closer interlayer structure compared with filtration self-assembly. Under the condition of similar chemical environment, the interlayer spacing can reach about 0.75 nm, which is reduced0.10 nm than that of filtration self-assembly GO membrane. The formation mechanism and rate are the main factors influencing the interlayer structure. The desalting experiment of the membrane for metallic cations/water solution showed that the rejection rate of the interface self-assembled GO membrane for Mg~(2+) was about 70%,which was 1.3 times of the self-assembly membrane.
引文
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