One-pot synthesis of N-doped graphene for metal-free advanced oxidation processes
One-pot synthesis of N-doped graphene for metal-free advanced oxidation processes
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DOI：
10.1016/j.carbon.2016.02.048
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发表时间：
2016-06
期刊：
影响因子：
10.9
通讯作者：
Chen Wang;Jian Kang;Hongqi Sun;H. Ang;M. Tadé;Shaobin Wang
中科院分区：
文献类型：
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作者：
Chen Wang;Jian Kang;Hongqi Sun;H. Ang;M. Tadé;Shaobin Wang
近年来，石墨烯及其衍生物作为一种新型的无金属材料在环境修复技术中引起了广泛的关注。实际应用的障碍之一是高质量石墨烯基催化剂的大规模生产。本研究以葡萄糖、氯化铁和尿素为原料，通过控制热解制备了高质量的氮掺杂石墨烯纳米材料。葡萄糖作为碳前体，尿素作为氮前体，六水合氯化铁作为模板和催化剂。发现在中等温度下实现了2- 4at%的低氧水平和0.5- 1.8at%的氮掺杂水平。采用所获得的氮掺杂的石墨烯作为无金属催化剂，用于通过过一硫酸盐（PMS）活化的有效苯酚降解。动力学研究表明，NG催化降解苯酚符合一级反应动力学。采用电子顺磁共振（EPR）技术检测纳米碳上PMS的自由基生成，以揭示PMS活化过程和苯酚降解途径的机理。结果表明，在苯酚的催化氧化过程中，产生了·OH和SO 4·−，并对苯酚的氧化起着重要作用。
Recently, graphene and its derivatives as novel metal-free materials have attracted considerable attention in environmental remediation technologies. One of the barriers to practical applications is the mass production of high quality graphene-based catalysts. In this study, high-quality nitrogen-doped graphene (NG) nanomaterials were synthesized by controlled pyrolysis of a mixture of glucose, ferric chloride and urea. Glucose serves as a carbon precursor, urea as a nitrogen precursor, and hexahydrate ferric chloride as both a template and a catalyst. It was found that a low oxygen level of 2–4 at% and a nitrogen doping level of 0.5–1.8 at% were achieved at a moderate temperature. The obtained nitrogen-doped graphene was employed as a metal-free catalyst for efficient phenol degradation by peroxymonosulfate (PMS) activation. Kinetic studies showed that the phenol degradation facilitated by NG catalysis followed first-order reaction kinetics. Electron paramagnetic resonance (EPR) was performed to detect radical generation in order to reveal the mechanism of PMS activation processes and phenol degradation pathways on nanocarbons. It was found that both •OH and SO4•−were produced in the catalytic oxidation processes and played significant roles in phenol oxidation.