可见光催化剂g-C3N4调控超亲水仿生纳滤膜微结构及协同催化机制

The surface modification of nanofiltration (NF) membrane can significantly improve its removal efficiency to the micropollutants and antifouling properties. The bio-inspired modification technology by dopamine can favor the formation of a superhydrophilic composite layer on membrane surface to reduce the deposition of organic pollutants, covering the shortage of the current modification approaches (e.g., dip-coating, grafting co-polymerization, layer-by-layer self-assembly, plasma treatment and blending). This study, based on the photocatalytic property of graphene-like carbon nitride (g-C3N4), proposes the strategy of g-C3N4 film with 2D nano-channel assisted photocatalysis to induce the polymerization of dopamine for the fabrication of novel bio-inspired NF membrane with antifouling, precise separation and photocatalysis properties. The study will firstly investigate the kinetics of dopamine polymerization induced by highly hydrophilic g-C3N4 and its immobilization procedure to demonstrate the mechanism for rapid polymerization of dopamine assisted by photocatalysis, facilitating to optimize the fabrication condition of the multi-functional bio-inspired NF membrane. Furthermore, the fabricated bio-inspired NF membrane will be applied to study its antifouling property, separation efficiency and degradation kinetics, revealing the synergistic mechanism for the removal of various organic pollutants. The results of this study will offer a guideline for the structure design of novel multi-functional NF membranes and advanced wastewater treatment.

表面改性纳滤膜可显著提高膜对水体微量污染物的去除效果和抗污染性能。多巴胺仿生修饰技术，通过在膜表面形成超亲水仿生层，以降低有机污染物的附着，从而弥补现有膜表面改性方法（表面涂覆、接枝共聚、层层自组装、等离子处理、掺杂共混等）的不足。本项目基于石墨相氮化碳（g-C3N4）纳米片的可见光催化特性，提出“以g-C3N4薄膜二维纳米通道可见光催化方法”诱导多巴胺快速聚合，制备新型仿生纳滤膜，实现抗污染、精确分离、催化等多重功能。为此，项目首先研究高亲水g-C3N4可见光催化剂引发多巴胺聚合的反应动力学及其固定化机制，阐明可见光催化引发多巴胺快速聚合反应的调控机理，优化多功能仿生纳滤膜的制备工艺条件；继而将制备的多功能仿生纳滤膜应用于多种有机污染物的去除，研究其抗污染性能、分离效率和对有机污染物的降解动力学，揭示仿生纳滤膜的多功能协同作用机制，为新型多功能纳滤膜的结构设计和废水的深度处理提供新思路。

表面改性纳滤膜可显著提高膜对水体微量污染物的去除效果和抗污染性能。多巴胺仿生修饰技术，通过在膜表面形成超亲水仿生层，以降低有机污染物的附着，从而弥补现有膜表面改性方法（表面涂覆、接枝共聚、层层自组装、等离子处理、掺杂共混等）的不足。本项目结合多巴胺改性及C3N4纳米片光催化的特点，制备新型多功能纳滤膜，实现抗污染、精确分离、催化等多重功能，将制备的多功能纳滤膜应用于染料废水的处理，研究其抗污染性能、分离效率和对染料的降解机理，为新型多功能纳滤膜的结构设计和废水的深度处理提供新思路。