氮掺杂中空多孔碳材料活化过一硫酸盐催化降解双酚A

Activation of peroxymonosulfate for bisphenol A degradation by nitrogen-doped hollow porous carbon materials

在高级氧化(AOPs)过程中,合理设计出环境友好、稳定高效的催化剂对水污染降解具有重要意义。使用原位聚合的方法合成了氮掺杂中空多孔碳材料(NHPC),并将其作为催化降解双酚A(BPA)的过一硫酸盐(PMS)活化剂;结合动力学分析与多种表征手段,探究了结构缺陷、sp^(2)杂化碳、氧官能团和3种典型的N键构型(吡啶N、吡咯N和石墨N)等因素对催化氧化反应性能的影响。BPA的反应速率常数与石墨N含量呈线性相关,表明石墨N是主要活性位点。同时,热处理可以通过再生石墨N来恢复催化剂活性,再生后的催化剂性能优于未使用的催化剂。自由基猝灭实验和电化学测试分析确定了NHPC-800/PMS体系主要是通过超氧自由基(O_(2)^(·-))介导的自由基过程降解双酚A(BPA)。加深了对氮掺杂碳基催化剂活化过硫酸盐的理解,对其在环境修复中的实际应用具有指导意义。

A rational design of economical,high-efficient and stable catalysts plays an important role in the degradation of water contaminants during advanced oxidations(AOPs).The N-doped hollow porous carbon materials(NHPC)are synthesized using an in-situ polymerization strategy,and then employed as peroxymonosulfate(PMS)activator for bisphenol A(BPA)degradation.Combined with kinetic analysis and various characterization methods,the effects of structural defects,sp^(2)-hybridized carbon,oxygen functional groups and three typical N-bonding configurations(pyridinic N,pyrrolic N and graphitic N)on the catalytic oxidation ability are investigated.A positive linear correlation between reaction rate con-stants and the content of graphitic N in NHPC reveals that the graphitic N are the main active sites for PMS activation.Meanwhile,the activity of catalyst can be recovered through heat treatment by regenera-ting graphite N,and the recovered catalyst exhibits more excellent activation performance than fresh catalyst.Furthermore,the free radical quenching experiments and electrochemical experiments demonstrate that the NHPC-800/PMS system decompose the BPA via O_(2)^(·-)-mediated radical processes.This study deepens the understanding of the N-doped carbon catalysts for PMS activation mechanism,providing guidance for the practical application of them in environmental remediation.