A.J. Drexel Nanomaterials Institute and Department of Material Science and Engineering, Drexel University, 3141 Chestnut Street, Philadelphia, Pennsylvania 19104, USA.
Chem Soc Rev. 2015 Dec 7;44(23):8664-87. doi: 10.1039/c5cs00279f. Epub 2015 Sep 28.
Suspension or semi-solid electrodes have recently gained increased attention for large-scale applications such as grid energy storage, capacitive water deionization, and wastewater treatment. A suspension electrode is a multiphase material system comprised of an active (charge storing) material suspended in ionic solution (electrolyte). Gravimetrically, the electrolyte is the majority component and aids in physical transport of the active material. This principle enables, for the first time, scalability of electrochemical energy storage devices (supercapacitors and batteries) previously limited to small and medium scale applications. This critical review describes the ongoing material challenges encompassing suspension-based systems. The research described here combines classical aspects of electrochemistry, colloidal science, material science, fluid mechanics, and rheology to describe ion and charge percolation, adsorption of ions, and redox charge storage processes in suspension electrodes. This review summarizes the growing inventory of material systems, methods and practices used to characterize suspension electrodes, and describes universal material system properties (rheological, electrical, and electrochemical) that are pivotal in the design of high performing systems. A discussion of the primary challenges and future research directions is included.
悬浮或半固态电极最近在大规模应用中受到越来越多的关注，例如电网储能、电容去离子和废水处理。悬浮电极是一种多相材料系统，由悬浮在离子溶液（电解质）中的活性（电荷存储）材料组成。从重量上看，电解质是主要成分，并有助于活性材料的物理传输。这一原理首次实现了电化学储能设备（超级电容器和电池）的可扩展性，这些设备以前仅限于中小规模应用。这篇重要的综述描述了涵盖基于悬浮液的系统的正在进行的材料挑战。这里描述的研究结合了电化学、胶体科学、材料科学、流体力学和流变学的经典方面，描述了悬浮电极中的离子和电荷渗滤、离子吸附和氧化还原电荷存储过程。本综述总结了日益增长的悬浮电极材料体系、用于表征悬浮电极的方法和实践，并描述了在高性能体系设计中至关重要的通用材料体系特性（流变学、电学和电化学）。讨论了主要挑战和未来的研究方向。
