Molecular Tuning of Redox-Copolymers for Selective Electrochemical Remediation
Molecular Tuning of Redox-Copolymers for Selective Electrochemical Remediation
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DOI：
10.1002/adfm.202004635
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发表时间：
2020-09-16
影响因子：
19
通讯作者：
Su, Xiao
中科院分区：
文献类型：
--
作者：
Kim, Kwiyong;Baldaguez Medina, Paola;Su, Xiao
氧化还原材料的分子设计为调节物理化学性质提供了一种很有前途的技术，而物理化学性质是选择性分离和环境修复的关键。本文研究了氧化还原共聚物4-methacryloyloxy-2，2，6，6-tetramethylpiperidin-1-oxyl(TMA)和4-methacryloyloxy-2，2，6，6-tetramethylpiperidine(TMPMA)的结构调节，用于选择性分离从全氟化合物到卤代芳香族化合物的各种阴离子污染物。胺官能团对阴离子官能团具有很高的亲和力，而氧化还原活性的氮氧基则促进了电化学控制的捕获和释放。通过控制胺和硝基的比例，可以调节共聚物的氧化还原活性、疏水性和结合亲和力，从而协同增强吸附和再生。P(TMA(X)-co-TMPMA(1-)(X))去除模型全氟化合物(全氟辛酸(PFOA))，具有很高的吸附容量(>；1000 mg g(-1))和分离因子(500 vs氯)，并在不同的水基质中对各种全氟烷基物质(PFAS)和卤代芳香化合物表现出极高的去除效率。与掺硼钻石电极的集成允许在同一个电化学池中串联分离和销毁污染物，从而实现分离步骤与催化降解步骤的能量整合。这项研究首次展示了氧化还原共聚物的调谐，用于选择性修复有机阴离子，并与先进的电化学氧化工艺相集成，以实现高效节能的水净化。
Molecular design of redox-materials provides a promising technique for tuning physicochemical properties which are critical for selective separations and environmental remediation. Here, the structural tuning of redox-copolymers, 4-methacryloyloxy-2,2,6,6-tetramethylpiperidin-1-oxyl (TMA) and 4-methacryloyloxy-2,2,6,6-tetramethylpiperidine (TMPMA), denoted as P(TMA(x)-co-TMPMA(1-)(x)), is investigated for the selective separation of anion contaminants ranging from perfluorinated substances to halogenated aromatic compounds. The amine functional groups provide high affinity toward anionic functionalities, while the redox-active nitroxyl radical groups promote electrochemically-controlled capture and release. Controlling the ratio of amines to nitroxyl radicals provides a pathway for tuning the redox-activity, hydrophobicity, and binding affinity of the copolymer, to synergistically enhance adsorption and regeneration. P(TMA(x)-co-TMPMA(1-)(x)) removes a model perfluorinated compound (perfluorooctanoic acid (PFOA)) with a high uptake capacity (>1000 mg g(-1)) and separation factors (500 vs chloride), and demonstrates exceptional removal efficiencies in diverse per- and polyfluoroalkyl substances (PFAS) and halogenated aromatic compounds, in various water matrices. Integration with a boron-doped diamond electrode allows for tandem separation and destruction of pollutants within the same electrochemical cell, enabling the energy integration of the separation step with the catalytic degradation step. The study demonstrates for the first time the tuning of redox-copolymers for selective remediation of organic anions, and integration with an advanced electrochemical oxidation process for energy-efficient water purification.