Abstract Water pollution and freshwater scarcity are two of the most important environmental problems faced by human around the globe in the 21st century. Capacitive deionization (CDI), as a promising electrochemical water treatment technology, has attracted large attention over the past decade for the facile removal of ions from water with the advantages of environmental friendliness, cost effectiveness, low energy consumption, and convenient electrode regeneration. Enormous progress has been made in the CDI research field and now CDI encompasses various cell architectures assembled with either capacitive electrodes or battery electrodes. These scientific advances are accompanied by a diverse application of CDI-based technologies. This work is intended to summarize the versatile applications of CDI and highlight the representative achievements in each of the applications primarily covering water desalination, water purification, water disinfection, resource recovery and synergistic combination with other technologies. Emerging application areas of CDI such as energy harvesting and CO2 capture are also presented. Lastly, the challenges and future outlook for CDI practical applications are discussed. This work should be of value in promoting CDI-based technologies to develop into a competitive option for coping with multiple water or energy-related issues.

中文翻译：

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基于电容去离子 (CDI) 的技术的多功能应用

摘要 水污染和淡水短缺是21世纪全球人类面临的两个最重要的环境问题。电容去离子（CDI）作为一种很有前途的电化学水处理技术，在过去十年中因其环境友好、成本效益高、能耗低、电极再生方便等优点，可轻松去除水中的离子，引起了广泛的关注。CDI 研究领域取得了巨大进展，现在 CDI 涵盖了由电容电极或电池电极组装的各种电池结构。这些科学进步伴随着基于 CDI 的技术的多样化应用。本工作旨在总结 CDI 的多功能应用，并突出每个应用中的代表性成果，主要涵盖海水淡化、水净化、水消毒、资源回收以及与其他技术的协同组合。还介绍了 CDI 的新兴应用领域，例如能量收集和二氧化碳捕获。最后，讨论了 CDI 实际应用的挑战和未来前景。这项工作对于促进基于 CDI 的技术发展成为应对多种水或能源相关问题的有竞争力的选择应该具有价值。还介绍了 CDI 的新兴应用领域，例如能量收集和二氧化碳捕获。最后，讨论了 CDI 实际应用的挑战和未来前景。这项工作对于促进基于 CDI 的技术发展成为应对多种水或能源相关问题的有竞争力的选择应该具有价值。还介绍了 CDI 的新兴应用领域，例如能量收集和二氧化碳捕获。最后，讨论了 CDI 实际应用的挑战和未来前景。这项工作对于促进基于 CDI 的技术发展成为应对多种水或能源相关问题的有竞争力的选择应该具有价值。