The global society is in a transition, where dealing with climate change and water scarcity are important challenges. More efficient separations of chemical species are essential to reduce energy consumption and to provide more reliable access to clean water. Here, membranes with advanced functionalities that go beyond standard separation properties can play a key role. This includes relevant functionalities, such as stimuli-responsiveness, fouling control, stability, specific selectivity, sustainability, and antimicrobial activity. Polyelectrolytes and their complexes are an especially promising system to provide advanced membrane functionalities. Here, we have reviewed recent work where advanced membrane properties stem directly from the material properties provided by polyelectrolytes. This work highlights the versatility of polyelectrolyte-based membrane modifications, where polyelectrolytes are not only applied as single layers, including brushes, but also as more complex polyelectrolyte multilayers on both porous membrane supports and dense membranes. Moreover, free-standing membranes can also be produced completely from aqueous polyelectrolyte solutions allowing much more sustainable approaches to membrane fabrication. The Review demonstrates the promise that polyelectrolytes and their complexes hold for next-generation membranes with advanced properties, while it also provides a clear outlook on the future of this promising field.

中文翻译：

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聚电解质作为具有先进功能的下一代膜的构建模块

全球社会正处于转型期，应对气候变化和水资源短缺是重要挑战。更有效地分离化学物质对于减少能源消耗和提供更可靠的清洁水供应至关重要。在这里，具有超越标准分离特性的先进功能的膜可以发挥关键作用。这包括相关功能，例如刺激响应性、污垢控制、稳定性、特异性选择性、可持续性和抗菌活性。聚电解质及其复合物是一种特别有前途的系统，可以提供先进的膜功能。在这里，我们回顾了最近的工作，其中先进的膜性能直接源于聚电解质提供的材料性能。这项工作强调了基于聚电解质的膜改性的多功能性，其中聚电解质不仅可以作为单层（包括刷）应用，还可以作为更复杂的聚电解质多层应用在多孔膜支撑物和致密膜上。此外，独立式膜也可以完全由聚电解质水溶液生产，从而实现更可持续的膜制造方法。该评论展示了聚电解质及其复合物对具有先进性能的下一代膜的前景，同时也为这一前景广阔的领域的未来提供了清晰的前景。