氮杂质缺陷碳助催化剂增效类芬顿反应过程机制  

Mechanism of nitrogen impurity defect carbon promoter enhanced fenton-like reaction process

作　　者：高位正 钱征 陈荣志 田雨佳 杨生炯[1] GAO Weizheng;QIAN Zheng;CHEN Rongzhi;TIAN Yujia;YANG Shengjiong(School of Environmental and Municipal Engineering,Xi’an University of Architecture and Technology,Xi’an 710055,China;College of Resources and Environment,University of Chinese Academy of Sciences,Beijing 100049,China)

机构地区：[1]西安建筑科技大学环境与市政工程学院,西安710055 [2]中国科学院大学资源与环境学院,北京100049

出　　处：《环境工程学报》2024年第7期1849-1859,共11页Chinese Journal of Environmental Engineering

基　　金：陕西省自然科学基础研究计划面上项目(2024JC-YBMS-270)。

摘　　要：本研究以ZIF-8为模板制备了一系列氮掺杂碳材料,分析其对Fe^(3+)/H_(2)O_(2)体系的助催化性能与作用机制。使用X射线衍射仪、傅里叶红外光谱仪、拉曼光谱仪、X射线光电子能谱仪等手段,对助催化剂物相、形貌特征以及化学组分进行了详细分析。结果表明,所制备的助催化剂具有丰富的吡啶氮类杂质缺陷点位,且缺陷丰度随助催化剂制备温度的升高而下降;污染物降解实验表明,助催化剂的投加可显著增强Fe^(3+)向Fe^(2+)的还原,从而强化芬顿氧化体系对共存有机物的降解性能;顺磁共振分析、活性物种淬灭与电化学等实验表明,反应体系中共存有·OH、·O_(2)^(-)、^(1)O_(2)等活性物种,其中,·OH对共存污染物的降解起主导作用;通过X射线光电子能谱分析与量子化学计算对助催化过程机制进行了详细分析,结果表明,芬顿反应过程中失活催化组分(Fe^(3+))在助催化剂氮缺陷处的吸附伴随了由助催化剂向吸附态Fe^(3+)的电子传递过程,是Fe^(2+)再生的主要原因。以上研究结果可为缓解芬顿反应中Fe^(3+)/Fe^(2+)循环效率低的关键问题提供全新的思路,对碳基环境功能材料与芬顿氧化技术的耦合与应用可提供数据支撑。This study prepared a series of nitrogen-doped carbon materials by using ZIF-8 as a template to investigate their promotion performance and catalytic mechanism toward Fe^(3+)/H_(2)O_(2) system.The physical phase,morphological characteristics,and chemical composition of the promotor were analyzed with X-ray diffraction,Fourier transform infrared spectroscopy,Raman spectroscopy,and X-ray photoelectron spectroscopy.The results showed that the prepared promotor was abundant in pyridinic-nitrogen extrinsic defects,and the defect degree decreased with the increase of pyrolysis temperature during synthesis.Pollutant degradation experiments demonstrated that the addition of the promoter significantly facilitated the regeneration of Fe^(2+)from Fe^(3+),and strengthened the performance of Fenton matrix on the degradation of coexisting organic compounds.Electron paramagnetic resonance analysis,reactive oxidation species(ROS)quenching,and electrochemical experiments indicated that ROS such as·OH,·O_(2)^(-),and ^(1)O_(2) were involved in the reaction system,of which·OH played a major role.Detailed analysis of the promotion mechanism was conducted through X-ray photoelectron spectroscopy and quantum chemical calculations.The results indicated that the adsorption of Fe^(3+)onto nitrogen defects on the surface of the promoter was accompanied by an electron transfer process from the promoter to adsorbed Fe^(3+),which was responsible for the regeneration of Fe^(2+).These findings provided a novel approach to addressing the key issue of low Fe^(3+)/Fe^(2+)cycling efficiency in the Fenton reaction,and provide a theoretical and data support for the coupling and application of carbon-based environmental functional materials with Fenton oxidation technology.

关 键 词：助催化剂 芬顿氧化 碳缺陷 活性物种 

分 类 号：X703[环境科学与工程—环境工程]