Graduate Institute of Environmental Engineering, National Taiwan University, Taipei, 10617, Taiwan.
Department of Environmental Science & Engineering, Tunghai University, Taichung, 40704, Taiwan.
Chemosphere. 2016 Mar;146:113-20. doi: 10.1016/j.chemosphere.2015.12.012. Epub 2015 Dec 20.
In this study, a multiwalled carbon nanotubes-chitosan (CNTs-CS) composite electrode was fabricated to enable water purification by electrosorption. The CNTs-CS composite electrode was shown to possess excellent capacitive behaviors and good pore accessibility by electrochemical impedance spectroscopy, galvanostatic charge-discharge, and cyclic voltammetry measurements in 1 M H2SO4 electrolyte. Moreover, the CNTs-CS composite electrode showed promising performance for capacitive water desalination. At an electric potential of 1.2 V, the electrosorption capacity and electrosorption rate of NaCl ions on the CNTs-CS composite electrode were determined to be 10.7 mg g(-1) and 0.051 min(-1), respectively, which were considerably higher than those of conventional activated electrodes. The improved electrosorption performance could be ascribed to the existence of mesopores. Additionally, the feasibility of electrosorptive removal of aniline from an aqueous solution has been demonstrated. Upon polarization at 0.6 V, the CNTs-CS composite electrode had a larger electrosorption capacity of 26.4 mg g(-1) and a higher electrosorption rate of 0.006 min(-1) for aniline compared with the open circuit condition. The enhanced adsorption resulted from the improved affinity between aniline and the electrode under electrochemical assistance involving a nonfaradic process. Consequently, the CNT-CS composite electrode, exhibiting typical double-layer capacitor behavior and a sufficient potential range, can be a potential electrode material for application in the electrosorption process.
在这项研究中，制备了一种多壁碳纳米管-壳聚糖（CNTs-CS）复合电极，以通过电吸附实现水净化。通过在 1 M H2SO4 电解质中进行电化学阻抗谱、恒电流充放电和循环伏安法测量，表明 CNTs-CS 复合电极具有优异的电容行为和良好的孔可及性。此外，CNTs-CS 复合电极在电容脱盐方面表现出了有前景的性能。在 1.2 V 的电势下，CNTs-CS 复合电极上 NaCl 离子的电吸附容量和电吸附速率分别为 10.7 mg g(-1)和 0.051 min(-1)，明显高于传统的活性电极。改进的电吸附性能可归因于中孔的存在。此外，还证明了 CNTs-CS 复合电极从水溶液中电吸附去除苯胺的可行性。在 0.6 V 的极化下，与开路条件相比，CNTs-CS 复合电极对苯胺的电吸附容量为 26.4 mg g(-1)，电吸附速率为 0.006 min(-1)，更大和更高。在电化学辅助下涉及非 Faradic 过程的情况下，改善了苯胺与电极之间的亲和力，从而导致了增强的吸附。因此，具有典型双层电容器行为和足够电位范围的 CNT-CS 复合电极可以成为电吸附过程中应用的潜在电极材料。
