氮掺杂石墨烯的制备及其电催化氧气还原性能  

Synthesis of nitrogen-doped graphene and its catalytic activity for the oxygen reduction reaction in fuel cells

作　　者：马贵香[1,2] 赵江红[1] 郑剑锋[1] 朱珍平[1] 

机构地区：[1]中国科学院山西煤炭化学研究所煤转化国家重点实验室,山西太原030001 [2]中国科学院研究生院,北京100049

出　　处：《新型炭材料》2012年第4期258-265,共8页New Carbon Materials

摘　　要：通过改良Hummers法制备氧化石墨(Graphite oxide,GO),采用爆炸辅助还原法将GO还原剥离并原位掺杂得到氮掺杂石墨烯(Nitrogen-doped graphene,N-RGO)。采用TEM、SEM、FI-IR、XPS、XRD及Raman等分析手段对N-RGO的形貌、组成以及结构进行了表征,利用旋转环盘电极技术测试了其电催化氧气还原活性。TEM和SEM结果表明,爆炸条件下GO被很好地剥离开来,得到只有几层厚度的石墨烯;FI-IR及XPS结果表明,GO中大部分含氧官能团被脱除,C/O原子比达到26.2,是目前所得GO还原程度非常高的方法之一,且氮元素成功掺杂进石墨烯晶格中,掺杂氮的原子质量分数约为2.11%;电化学测试结果显示,氧气还原的极限扩散电流由非氮掺杂石墨烯(Reduced graphene oxide,RGO)的0.24mA提高到N-RGO的0.49 mA,尽管爆炸辅助还原得到的RGO对氧气还原也显示出较好的催化活性,但掺杂之后的N-RGO具有更高的催化活性。Graphene was synthesized by the detonation-assisted reduction of graphite oxide（GO） prepared by the modified Hummers method.Nitrogen-doped reduced GO（N-RGO）was obtained through an in-situ nitrogen-doping during detonation.The morphology,elemental composition and structure of the N-RGO were characterized by TEM,SEM,IR,XPS,XRD and Raman spectroscopy.The catalytic activity of the N-RGO as a fuel cell electrode for the oxygen reduction reaction（ORR） was investigated by a rotating ring disk electrode technique.Results showed that the GO was exfoliated and reduced to few layer graphene by the detonation.The oxygen-containing species of GO were reduced and the C/O molar ratio was increased to 26.2,which is much higher than for RGO.Nitrogen,as high as 2.11 at%,was incorporated into the graphene structure.The diffusion-limited current for ORR increased from 0.24 mA for RGO to 0.49 mA for N-RGO,indicating a higher catalytic activity of N-RGO for ORR than that of RGO.

关 键 词：爆炸 氧化石墨 氮掺杂石墨烯 氧气还原 

分 类 号：O613.71[理学—无机化学]