分级多孔SiOC负载g-C3N4复合材料的设计合成及其吸附-光催化降解机制研究

Porous ceramics used for absorbing materials have some problems such as low adsorption rate, long adsorption time and degradation of organic pollutants difficultly, which limit their applications in the field of wastewater treatment. This project conducts research for the difficult problem, proposing that hierarchical porous SiOC/g-C3N4 composites with low-cost and high-performance were prepared for the realization of the coupling of hierarchical porous structure and function of adsorption-photocatalytic degradation of organic pollutants, using biological templates and etching technology to prepare hierarchical porous PCDs, then followed by compositing with g-C3N4 to achieve the immobilization and modification of photocatalyst. In order to achieve the purpose of efficient adsorption and degradation of organic pollutants, this project proposed to study on three aspects: design optimization of hierarchical porous structure of SiOC, modification of photocatalyst, synergy between adsorption and photocatalytic properties. By examining the influence of the ratios of raw materials, pyrolysis temperatures, modification methods on the structure, adsorption and photocatalytic properties of the composites, the structure-activity relationship of the composites were confirmed. The mechanism of adsorption-photocatalytic degradation and synergistic mechanism of adsorption-photocatalytic of the composites were explored. This study of the project provides the new technology and theory reference for the preparation and applications of porous PCDs matrix composites with low-cost and high-performance.

多孔陶瓷普遍存在吸附率低、吸附时间长、降解有机污染物困难等问题，限制其在污水处理领域的应用。本项目针对此难点问题开展研究，提出采用生物模板法及刻蚀技术制备分级多孔聚合物衍生陶瓷(PCDs)，与石墨相氮化碳(g-C3N4)复合实现光催化剂的固载与改性，从而合成低成本、高性能的分级多孔SiOC/g-C3N4复合材料，实现复合材料的分级多孔结构与吸附-光催化降解有机污染物功能的耦合。为了达到高效吸附降解有机污染物的目的，拟分别从SiOC分级多孔结构的设计优化、g-C3N4的改性及复合材料的吸附-光催化协同作用三方面开展研究工作。通过考察原料配比、裂解温度、改性手段等对复合材料结构、吸附性能及光催化性能等的影响，阐明复合材料的结构与吸附-光催化性能间的构效关系，揭示复合材料的吸附-光催化降解机理及协同作用机制，为低成本、高性能多孔PCDs基复合材料的制备及其应用提供新的技术和理论参考。

开发低成本、高性能、可循环利用的先进污水处理材料成为当前环境领域的研究热点。本项目以高效去除水体中环境污染物为目标，以揭示复合材料的吸附-光催化协同作用机制作为基础科学问题，采用生物模板法设计构筑了分级多孔SiOC陶瓷，与石墨相氮化碳(g-C3N4)复合合成出多孔SiOC/g-C3N4复合材料，实现复合材料的吸附-光催化降解有机污染物功能的耦合。获得了模板种类、工艺条件等对SiOC陶瓷载体的组成、结构及吸附性能的影响，建立了SiOC陶瓷的吸附等温线模型、吸附动力学方程，确定了影响其吸附行为的关键因素；获得了影响多孔SiOC/g-C3N4复合材料组成、结构、吸附及光催化性能的关键因素，揭示出复合材组成、结构与光催化性能间的相互关系，建立了分级多孔SiOC/g-C3N4复合材料在可见光条件下光催化降解不同结构有机污染物的动力学方程，揭示了不同结构有机污染物在光催化高级氧化过程中的转化机理，实现复合材料的吸附-光催化协同作用。项目已在国内外重要期刊发表论文11篇，其中SCI论文10篇，EI论文1篇，授权发明专利1项，申请发明专利4项，培养硕士生5人。