Department of Applied Physics, School of Science, Campus Fuentenueva University of Granada , 18071 Granada, Spain.
Environ Sci Technol. 2017 May 2;51(9):5326-5333. doi: 10.1021/acs.est.6b06181. Epub 2017 Apr 11.
All efforts to obtain, reuse or purify water are extremely significant for society. Recently, researchers have begun to delve in an idea born decades ago: the desalination of water using highly porous electrodes. It is based on a fundamental aspect of electrical double layers, namely, their huge capacitance. The ions of a solution can be partially removed under the application of an electric field when the solution fills the space between porous electrodes, either bare (CDI, or capacitive deionization), coated with ionic exchange membranes (MCDI) or chemically treated (inverted-CDI or i-CDI). One of the challenges of the last years was to explore new materials and arrangements to improve the efficiency of the system. In this work, we propose a new approach inspired in the electrokinetics of soft particles: a layer of polyelectrolyte (cationic on one electrode, anionic on the opposite one) coats the carbon electrodes, converting them in a sort of "soft" electrode pair. We present a theoretical model and a set of experiments showing how soft electrodes can be successfully employed in capacitive deionization.
为社会获取、再利用或净化水所做的一切努力都是极其重要的。最近，研究人员开始深入研究一个几十年前诞生的想法：利用高多孔电极淡化海水。它基于双电层的一个基本方面，即其巨大的电容。当溶液充满多孔电极之间的空间时，在电场的作用下，可以部分去除溶液中的离子，无论是裸电极（CDI，或电容去离子）、涂有离子交换膜（MCDI）还是经过化学处理（倒转 CDI 或 i-CDI）。近年来的挑战之一是探索新的材料和布置方式来提高系统的效率。在这项工作中，我们提出了一种受软粒子电动学启发的新方法：一层聚电解质（在一个电极上带正电荷，在另一个电极上带负电荷）涂覆在碳电极上，将它们变成一种“软”电极对。我们提出了一个理论模型和一组实验，展示了软电极如何成功地应用于电容去离子化。
