基于PCN表面官能团设计的水泥基复合材料长期光催化功效提升机制

提升长期光催化功效是光催化水泥基复合材料（PCC）推广应用的前提。本项目拟从光催化材料表面官能团改性的角度探究提升PCC长期光催化功效的理论与方法。选用不同类型和含量表面官能团修饰的氮化碳聚合物（PCN）作为光催化剂，围绕影响PCC长期光催化功效的三个关键性能，研究不同表面官能团PCN与基体之间的抗剥离性能，揭示不同表面官能团PCN与水化产物分子间作用机制；研究不同表面官能团PCN对PCC耐磨性能和抗碳化性能的影响规律，阐明不同表面官能团PCN对水化产物组成、形貌、水化程度和微结构的影响机理。通过探究PCC在水冲刷、磨损和碳化耦合作用下的光催化去除氮氧化物性能评估其长期光催化功效，建立PCN表面官能团类型和含量与PCC关键性能以及长期光催化功效之间的定量关系，提出基于PCN表面官能团设计的PCC长期光催化功效提升理论与方法。研究成果将为推广PCC的工程应用提供理论指导和技术支撑。

Improvement of long-term photocatalytic efficiency is the prerequisite for the large-scale application of photocatalytic cement-based composites (PCC). This project innovatively proposes to explore the improvement theory and method of long-term photocatalytic performance of PCC based on modification of surface functional groups of photocatalyst. Different types and contents of surface functional groups modified carbon nitride polymers (PCN) will be used as photocatalysts. Three key properties that determine the long-term photocatalytic performance of PCC will be fully investigated. The peel resistance between PCN with different surface functional groups and matrix will be studied, and the interaction mechanism between different surface functional groups modified PCN and hydration products will be subsequently revealed. The influence of different surface functional groups modified PCN on the abrasion resistance and carbonization resistance of PCC will be studied, and the effect mechanism of PCN with different surface functional groups on the composition, morphology, hydration degree and microstructure of hydration products will be clarified. The long-term photocatalytic performance of PCC will be evaluated by determination of the photocatalytic removal of nitrogen oxides under coupling effects of water washing, mechanical abrasion and carbonization. Based on the above obtained results, the quantitative relationship between the types and contents of surface functional groups of PCN and the key properties and long-term photocatalytic performance of PCC will be established, and the theory and approach for improving the long-term photocatalytic performance of PCC based on the surface functional groups of PCN will be consequently proposed. The research results will provide theoretical guidance and technical support for the engineering application of PCC.