巯基化石墨烯/碳纳米管/三聚氰胺泡沫复合电极的制备及在电吸附除铜中的应用

Preparation of TrGO/Multi Walled Carbon Nanotubes/Melamine Foam Composite Electrode and Its Application in Electrosorption of Copper

通过将一定量的多壁碳纳米管(MWCNT)与氧化石墨烯(GO)水溶液混合,以硫氢化钠(NaSH)为改性剂,三聚氰胺泡沫(MF)为复合材料的骨架,制备出带有巯基(-SH)的TrGO/MWCNT/MF复合电极。利用扫描电镜(SEM)、X射线光电子能谱(XPS)和循环伏安法(CV)分别研究了复合电极的形貌特征、化学结构和电化学性能。在静电场的作用下,用TrGO/MWCNT/MF电极吸附水中的铜离子,结果表明,在铜离子溶液浓度为250 mg/L、pH为5.5和电压为0.8 V时,吸附平衡容量能达到227.06 mg/g。此外,还考察了TrGO/MWCNT/MF电极吸附铜离子的机理,发现该电极吸附过程符合Pseudo-second-order动力学模型与Freundlich等温模型。重要的是,该复合电极在6次电吸-脱附后表现出较好的循环再生性能。

A TrGO/MWCNT/MF electrode with sulfhydryl group(-SH)was prepared by mixing a certain amount of multi walled carbon nanotubes(MWCNT)and graphene oxide(GO)solution,using sodium hydrogen sulfide(NaSH)as modifier and melamine foam(MF)as skeleton of composite.Scanning electron microscopy(SEM),X-ray diffractometer(XPS)and cyclic voltammetry(CV)were used to study the morphological characteristics,chemical structure and electrochemical performance of the electrode,respectively.Under the action of electrostatic field,the TrGO/MWCNT/MF composite electrode was used to adsorb Cu2+in water.The results show that when the concentration of Cu2+solution is 250 mg/L,pH is 5.5 and the voltage is 0.8 V,the adsorption equilibrium capacity could reach 227.06 mg/g.In addition,the adsorption mechanism of TrGO/MWCNT/MF electrode for Cu2+was also investigated.It is found that the adsorption process is in accordance with the pseudo second order kinetic model and Freundlich isothermal model.Importantly,the composite electrode exhibits good cycle regeneration performance after 6 electrosorption-desorption cycles.