Highly Efficient and Stable Capacitive Deionization Based on a Flower‐Like Conjugated Polymer with Double Active‐Sites

作者：Zhiyun Zhuang, Lei Sun, Yueheng Tao, Shao Jian, Jinggang Yang, Peng Yu, Huanxu Chen, Jianhua Zhou, Jing Xiao, Kangyong Yin, Minjie Shi, Peng Xiao · 发表于：Energy & environment materials · 年份：2024 · DOI：10.1002/eem2.12852 · 被引用次数：12 · 研究领域：Membrane-based Ion Separation Techniques、Membrane Separation Technologies、Advanced Battery Materials and Technologies

Hybrid capacitive deionization (HCDI) shows promise for desalinating brackish and saline water by utilizing the pseudocapacitive properties of faradaic electrodes. Organic materials, with their low environmental impact and adaptable structures, are attractive for this application. However, their scarcity of active sites and tendency to dissolve in water‐based solutions remain significant challenges. Herein, we synthesized a polynaphthalenequinoneimine (PCON) polymer with stable long‐range ordered framework and rough three‐dimensional floral surface morphology, along with high‐density active sites provided by C=O and C=N functional groups, enabling efficient redox reactions and achieving a high Na + capture capability. The synthesized PCON polymer showcases outstanding electroadsorption characteristics and notable structural robustness, attaining an impressive specific capacitance of 500.45 F g −1 at 1 A g −1 and maintaining 86.1% of its original capacitance following 5000 charge–discharge cycles. Benefiting from the superior pseudocapacitive properties of the PCON polymer, we have developed an HCDI system that not only exhibits exceptional salt removal capacity of 100.8 mg g −1 and a remarkable rapid average removal rate of 3.36 mg g −1 min −1 but also maintains 97% of its initial desalination capacity after 50 cycles, thereby distinguishing itself in the field of state‐of‐the‐art desalination technologies with its comprehensive performance that significantly surpasses report...