热处理温度对石墨烯/炭纳米复合纤维催化氧化NO性能的影响

The effect of the NH_3 activation temperature of graphene/carbon composite nanofibers on their NO catalytic oxidation performance at room temperature

以聚丙烯腈(PAN)为碳前驱体,氧化石墨烯(GO)为添加物,通过静电纺丝技术制备了石墨烯/炭纳米复合纤维原丝,分别在900、1 000、1 100和1 200℃下氨气中炭化10 min,并在NH_3中活化处理20 min得到多孔、N掺杂的石墨烯/炭纳米复合纤维。分别将4种样品用于室温下低浓度NO(50 ppm)的吸附和催化氧化研究。结果表明,复合纳米纤维对NO的催化氧化性能随着处理温度的升高而增强,在样品PGCNF1200达到最大转化率(49.7%),而对NO和NO2的吸附能力则强烈的依赖于纤维比表面积的大小。此外,经NH_3活化处理后可以在纤维表面引入含氮官能团,可以和作为催化活性位点的GO共同对室温下NO的催化氧化起到促进作用。

N-doped graphene/carbon composite porous nanofibers were prepared by electrospinning,followed by carbonization initrogen and activation in NH3 at 900,1 000,1 100 and 1 200 益 for 20 min,using polyacrylonitrile as a carbon precursor and graphene oxide as an additive. Their NO （50 ppm） adsorption and catalytic oxidation performances at room temperature were testedResults showed that the catalytic oxidation activity increased with the activation temperature and a maximum conversion of 49. 7 %was achieved for the sample activated at 1 200 益.The adsorption capacity for NO and NO2 depended on their specific surface areasThe nitrogen-containing functional groups introduced by NH3 and the active sites formed in graphene sheets jointly increased NO conversion at room temperature.