Shi Mingxing, Lu Keren, Jia Huijuan, Hong Xianyong, Yan Yanghao, Qiang Hua, Wang Fengyun, Xia Mingzhu
School of Chemistry and Chemical Engineering, Nanjing University of Science and Technology, Nanjing 210094, China.
School of Chemistry and Chemical Engineering, Nanjing University of Science and Technology, Nanjing 210094, China; Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore 637371, Singapore.
Sci Total Environ. 2023 Dec 15;904:167339. doi: 10.1016/j.scitotenv.2023.167339. Epub 2023 Sep 23.
The low carbon mass loading along with serious imbalance between the carbon mass loading and the electrode performance greatly hinders practical applications of capacitive deionization (CDI). Traditional thick bulk-type (BT) carbon electrodes often suffer from extremely limited active sites, thereby being vital to explore a basic strategy to unlock the performance. Herein, 3D-printed thick carbon electrodes were utilized for CDI desalination for the first time. The experimental outcomes revealed that BT electrodes existed a serious salt adsorption capacity (SAC) drop under variable mass loading of 3-30 mg/cm. In contrary, 3D-printed river-type (RT) electrodes acquired a superior SAC of 10.67 mg/g and achieved 54.1 % SAC rise compared with that of BT electrodes (500 mg/L; 1.0 V; 30 mg/cm). Meanwhile, RT electrodes took only 12 min to reach the equilibrium SAC of BT electrodes, being 44 min faster. Further, RT electrodes with diverse mass loading of 30-45 mg/cm were investigated, and it still kept 7.13 mg/g SAC under ultrahigh mass loading of 45 mg/cm. This strategy has been successfully extended and carbons with proper micro-meso pore distribution, high specific capacitances and low resistance may be a better selection. Besides, the impact of electrode channel structure on the desalting performance was investigated, and the influence mechanism was revealed via COMSOL simulation. Overall, this work demonstrates the splendid feasibility of utilizing 3D-printed thick carbon electrodes for possible practical application-level CDI desalination.
低碳质量负载以及碳质量负载与电极性能之间的严重失衡极大地阻碍了电容去离子化（CDI）的实际应用。传统的厚块体型（BT）碳电极通常存在活性位点极其有限的问题，因此探索一种解锁其性能的基本策略至关重要。在此，首次将3D打印的厚碳电极用于CDI脱盐。实验结果表明，在3 - 30 mg/cm的可变质量负载下，BT电极存在严重的盐吸附容量（SAC）下降。相反，3D打印的河流型（RT）电极获得了10.67 mg/g的优异SAC，与BT电极（500 mg/L；1.0 V；30 mg/cm）相比，SAC提高了54.1%。同时，RT电极仅需12分钟就能达到BT电极的平衡SAC，快了44分钟。此外，研究了质量负载为30 - 45 mg/cm的不同RT电极，在45 mg/cm的超高质量负载下，其SAC仍保持在7.13 mg/g。该策略已成功扩展，具有适当微孔 - 介孔分布、高比电容和低电阻的碳可能是更好的选择。此外，研究了电极通道结构对脱盐性能的影响，并通过COMSOL模拟揭示了其影响机制。总体而言，这项工作证明了利用3D打印的厚碳电极实现实际应用级CDI脱盐的卓越可行性。
