铁基氮掺杂碳纳米管制备及其电催化性能  

Preparation and Electrocatalytic Performance of Iron Based Nitrogen Doped Carbon Nanotubes

作　　者：李莉香[1,2] 赵宏伟[1] 许微微[1] 张砚秋[1] 安百钢[1,2] 耿新[1,2] 

机构地区：[1]辽宁科技大学化学工程学院,辽宁鞍山114051 [2]辽宁科技大学材料电化学研究所,辽宁鞍山114051

出　　处：《物理化学学报》2015年第3期498-504,共7页Acta Physico-Chimica Sinica

基　　金：国家自然科学基金(51102126);辽宁省高等学校创新团队(LT2014007);辽宁省高等学校杰出青年学者成长计划(LJQ2012026)资助项目~~

摘　　要：利用化学原位聚合法制备聚吡咯包覆碳纳米管,然后以硫酸亚铁铵盐为铁前驱体,采用液相沉淀法制备聚吡咯-碳纳米管-铁化合物复合材料(Fe-PPy-CNTs),通过对复合材料Fe-PPy-CNTs热处理,成功制备出铁基氮掺杂碳纳米管催化剂Fe NCNTs.X射线衍射分析表明,热处理使Fe-PPy-CNTs复合物中Fe3O4向Fe3N和Fe转化,700°C热处理制备的Fe NCNT700中铁主要是Fe3O4相,但也有Fe相.800和900°C热处理制备的催化剂Fe NCNT800和Fe NCNT900则明显有Fe3N和Fe形成.随着热处理温度升高,Fe NCNTs催化剂氮含量降低,其含氮官能团也由吡咯型氮向吡啶型和石墨型氮转化.电化学分析表明,含有Fe3N的Fe NCNT800和Fe NCNT900催化剂具有明显的氧还原催化活性,其中,Fe NCNT800因其具有高的比表面积、高的氮含量和高比例的有利于增强氧吸附能力和弱化O―O键的石墨氮官能团,而表现出优于Fe NCNT900氧还原催化活性及稳定性.Polypyrrole coated carbon nanotubes（PPy/CNTs） were synthesized by the in-situ chemical polymerization of pyrroles on CNTs. Iron compounds were deposited on the PPy/CNTs to form an Fe-PPy-CNTs composite using ferrous ammonium sulfate as the iron precursor by liquid phase precipitation. Catalysts wherein iron-based compounds were loaded onto nitrogen doped CNTs（Fe NCNTs） were prepared by heat treatment of the composites. X-ray diffraction（XRD） analysis shows that the heat treatment of Fe-PPy-CNTs caused the Fe3O4 in the composite to convert to Fe3 N and Fe. The Fe NCNT700 prepared at 700 °C contains Fe3O4 and Fe.We conclusively show that in both Fe NCNT800 and Fe NCNT900 that were prepared at 800 and 900 ° C,respectively, Fe3 N and Fe formed. With an increase in temperature the total amount of nitrogen in the Fe NCNTs decreases and the nitrogen containing functional groups convert from pyrrolyic-N to pyridinic-N and graphiticN. Electrochemical analyses show that the Fe NCNT800 and Fe NCNT900 that contain Fe3 N exhibits good activity toward the oxygen reduction reaction（ORR）. Compared with Fe NCNT900, Fe NCNT800 has better ORR activity and stability because of its larger specific surface area, higher nitrogen content and higher ratio of graphitic-N in the nitrogen containing functional groups. This enhances the oxygen adsorption ability of the catalyst and weakens the O―O bond.

关 键 词：氮掺杂 碳纳米管 铁 电催化 氧还原 

分 类 号：O643.36[理学—物理化学] TB383.1[理学—化学]