界面强化的银@石墨烯/几丁质多孔宏观纳米组装体的制备及用于水的杀菌消毒性能研究

Nowadays, the rapid development of nanotechnology provides feasible pathway to design new materials for water treatments. And meanwhile, study on how to exert the excellent performance of nanomaterials as well as avoiding their drawbacks became an important research area in materials science. This project proposes to prepare interfacial reinforced Ag@Graphene/chitin porous macroscopic assembly from nanomaterials via directional freezing for water disinfection. . In the first stage, this project plan to obtain large quantities of chitin nanofiber and graphene sheets by mechanical shearing exfoliation. Silver nanoparticles will be decorated on graphene sheets to provide active sites for modification and antimicrobial activities for final product. In order to enhance the interfacial interactions by introducing covalent bonds, chitin nanofiber and Ag@graphene composite sheets are going to be modified with specific functional groups to ensure “click” reaction between these two building blocks. In the second stage, directional freezing technique will be employed to assemble the above building blocks to form the macroscopic assembly with ordered channels. In our design, the diameter of the channel can be adjusted to ensure water infiltration. Meanwhile, the wall of the channel will display nacre-like lamellar microstructure to enhance the mechanical properties of the assembly. To optimize the water disinfection and mechanical performance, the structure of the material will be adjusted by controlling the assembly parameters. . The developing of such macroscopic assembly will provide a new strategy for water disinfection and microbial control, which is believed to avoid the disadvantages of using traditional methods and pure nanomaterials.

当前，纳米技术的快速发展为开发新型水处理材料带来了希望。研究如何既利用好纳米材料的优异性能，又避免使用单纯纳米材料的不足，是材料学领域的重要研究方向。本项目提出了制备界面强化的银@石墨烯/几丁质多孔宏观纳米组装体用于水杀菌消毒的新思路。拟利用高速机械剪切机宏量剥离获取几丁质纳米纤维和石墨烯，通过对几丁质和石墨烯分别修饰功能基团，利用“click”反应形成共价键，增强界面作用。并且，通过对石墨烯修饰纳米银实现水体的杀菌消毒。通过取向冷冻技术既可获得长程有序、大小可调的孔道，便于水的流通；又使材料孔壁呈现仿贝壳的“砖-泥”微结构，显著提高材料的机械性能。拟以水处理功能为导向，通过调控材料结构，优化机械和杀菌消毒性能，有望减少水的消毒中使用传统手段和单纯使用纳米材料带来的弊端。

纳米技术的快速发展为开发新型水处理材料带来了希望。为既利用好纳米材料的优异性能，又避免使用单纯纳米材料的不足，本项目积极探索基于天然高分子聚合物的仿生取向多孔支架和薄膜的组装制备和功能化，发展了一种宏观多孔模板和界面调控银基纳米线在蚕丝蛋白取向多孔支架上原位生长的方法，为利用蚕丝蛋白仿生支架调控多种纳米材料的原位合成和组装，以及构建蚕丝蛋白-纳米材料的功能性复合仿生支架提供新思路。所获得的仿生取向多孔支架不仅可用于高效水杀菌消毒，还具有良好的光吸收致热性能，可加速太阳能水蒸发获取洁净水。进一步设计制备了抗生物污损的取向多孔支架用于长效太阳能水蒸发和水处理。同时，设计构建了仿贝壳砖泥微结构的载银石墨烯-海藻酸钠薄膜和仿生几丁质纳米纤维取向多孔支架，验证了仿生微结构和天然大分子纳米纤维可用于力学性能强化。进一步，研究设计了磁响应可注射水凝胶和酶响应性的银纳米粒子组装体，为进一步优化增强纳米材料的仿生宏观组装体功能提供了思路。