湖南大学环境科学与工程学院唐旺旺研究组在研究中取得进展。他们研究出阶梯式空心FeHCFe纳米立方与二相聚吡咯在高效电化学海水淡化中的协同作用。这一研究成果发表在2025年2月10日出版的国际学术期刊《德国应用化学》上。

在此，研究人员创新地设计了一种复杂的普氏蓝/二态聚吡咯复合材料用于混合CDI （HCDI）。具体而言，纳米颗粒状聚吡咯（PPy）原位分布在阶梯状空心FeHCFe纳米立方上；而共存的纳米管状聚吡啶则连接了分立的阶梯空心FeHCFe纳米立方体。二相PPy的引入促进了FeHCFe的电子动力学和离子动力学，提高了FeHCFe的电化学活性。同时，独特的FeHCFe纳米立方体为电解质提供了更大的可接触面积，减少了Na⁺的迁移路径，提高了对晶格膨胀的耐受性，并优化了Na⁺存储的氧化还原位点。通过这种独特的结构设计和协同组合，FeHCFe/PPy取得了显著的脱盐能力，脱盐速度快于相关材料。

通过6个串联HCDI细胞，处理后的溶液在6分钟内达到饮用水标准。密度泛函理论（DFT）揭示了Na⁺的捕获机制，为Na⁺的快速迁移和大量Na⁺的储存提供了基础认识。本研究为高性能电化学海水淡化电极材料的合理设计提供了参考。

据了解，咸水淡化是增加淡水供应的重要途径，而电容去离子技术（CDI）已成为解决这一问题的一种很有前途的技术。为了促进CDI的成功，开发先进的电极材料是至关重要的。

附：英文原文

Title: Synergy from the Stepped Hollow FeHCFe Nanocubes and the Dimorphic Polypyrrole for High-Performance Electrochemical Water Desalination

Author: Yu Liu, Kunyue Luo, Wenle Xing, Wenjun Yin, Jing Feng, Shuaishuai Pi, Zixiao Kang, Jie Liang, Lin Tang, Wangwang Tang

Issue&Volume: 2025-02-10

Abstract: Saline water desalination is an important route to increase freshwater supply, while capacitive deionization (CDI) has emerged as a promising technique to tackle this issue. To boost the success of CDI, development of advanced electrode materials is vital. Herein, we innovatively designed a sophisticated Prussian blue/dimorphic polypyrrole composite for hybrid CDI (HCDI). Specifically, the nanoparticle-like polypyrrole (PPy) in-situ distributed on the stepped hollow FeHCFe nanocubes' surface, while coexisting nanotube-like PPy interconnected the discrete stepped hollow FeHCFe nanocubes. The introduction of dimorphic PPy promoted both electron and ion dynamics, and improved the electrochemical activity of FeHCFe. Meanwhile, the unique FeHCFe nanocubes offered large accessible contact area for electrolyte, reduced Na+ migration path, improved tolerance for lattice expansion, and optimized redox sites for Na+ storage. Through such unique structural design and synergistic combination, the FeHCFe/PPy achieved a remarkable desalination capacity and a fast desalination rate outperforming related materials. Moreover, the treated solution can meet drinking water standard within 6 min via six tandem HCDI cells. Density functional theory (DFT) revealed Na+ capture mechanism and provided fundamental understanding of the rapid Na+ migration and large Na+ storage. This study provides insights into ration design of superior electrode materials for high-performance electrochemical water desalination.

DOI: 10.1002/anie.202501797

Source: https://onlinelibrary.wiley.com/doi/10.1002/anie.202501797