氮掺杂碳/过渡金属复合材料的构建及其催化生成硫酸根自由基降解有机污染物研究

As one of high-efficiency and innovative water treatment technologies for degradation of organic pollutants，sulfate radical (SO4•-) based heterogeneous advanced oxidation processes (AOPs) have been of great interest in recent years. Unfortunately, most existing heterogeneous catalysts suffer from insufficient catalytic efficiency, low stability and complicated synthetic procedures. To address these obstacles, we hope to propose a facile and green method for fabrication of novel multifunctional catalyst with high catalytic activity and stability. This project focuses on the synthesis of transition metal nanoparticles-loaded nitrogen-doped carbon nanocomposites through one-step pyrolysis of precursor materials and their applications in catalytic generation of SO4•- for degradation of model pollutants (chlorophenols). The effects of various preparation conditions on the properties of catalysts as well as the catalytic performance and stability of different catalysts will be investigated to obtain an optimalizing material. Meanwhile, the functional mechanism of nanocomposite and the degradation pathway of pollutants in the system will be also researched on the basis of the results of diverse control experiments and characterizations. This study will help to achieve a stable and efficient heterogeneous catalytic oxidation system for degradation of organic pollutants and further provide scientific support for the practical application of SO4•- based AOPs.

非均相催化生成硫酸根自由基（SO4•-）降解有机污染物是近年来高级氧化技术的研究热点之一。为解决或改善现有非均相催化剂催化效率较低、稳定性差、制备方法复杂等问题，提出以绿色、可控的制备技术来构建具有高催化活性和稳定性的新型多功能非均相催化剂。研究拟采用一步热解前体材料的方法将氮掺杂碳材料与过渡金属原位杂化形成氮掺杂碳/过渡金属复合催化材料，并探明制备条件对催化剂性能的影响。以氯酚类化合物为模型污染物，研究不同前体材料制得的催化剂活化单过硫酸盐降解有机物的效率及其稳定性。结合降解实验和材料表征结果，探究复合材料中各组分间的协同作用机制，并揭示污染物氧化降解途径。本项目希望通过这些研究获得高效稳定、机制明确的有机污染物催化氧化技术体系，为SO4•-类高级氧化技术在污染物处理中的实际应用提供科学支持。

本项目针对现有非均相催化剂激活单过硫酸盐氧化有机污染物时效率较低、稳定性差、制备方法复杂等问题，开展了以简易、可控的制备技术来构筑具有高催化活性和稳定性的新型氮掺杂碳/过渡金属复合催化材料，并探究了以其为基础构建的氧化体系处理典型有机污染物的效能。主要依赖原位生长的策略，制得了组成、结构可调的氮掺杂碳/过渡金属复合催化剂（包括二维NRGO@Co和ZnCo2O4/g-C3N4、三维Fe/Fe3C@NC和介孔Fe/N共掺杂碳、中空HM-NC/CoFe2O4和MnOx/N-HPCS以及中空双层Fe/N/S三掺杂碳等材料），阐明了氮掺杂碳/过渡金属复合材料的形貌、催化剂组成与结构的调变规律。通过优化各种条件因素，构建了基于 SO4•-等活性物种生成的典型污染物高效氧化新体系。通过探讨反应体系中目标污染物的吸附降解及其转化行为、活性物种生成去向和赋存形态以及过渡金属和杂原子掺杂碳材料界面反应机制，揭示了污染物氧化降解途径及氮掺杂碳/过渡金属复合催化剂对目标污染物增效去除机理。在本项目的资助下，共发表学术论文13篇，其中包括在Chem. Commun.、Environ. Sci. Technol.、Appl. Catal. B-Environ.、J. Phys. Chem. C等重要期刊上发表SCI论文12篇，中文核心期刊1篇。申请发明专利4项。培养硕士研究生3人，其中1人获浙江省优秀硕士论文。