氮掺杂多壁碳纳米管的合成及NO电氧化研究

【作者】 吕伟欣；

【导师】 史克英；

【作者基本信息】 黑龙江大学 ， 物理化学， 2010， 硕士

【摘要】 本文以吡啶和酞菁铁为原料、以包含铁的化合物为催化剂,通过控制合成条件用CVD法制备了不同氮含量的氮掺杂多壁碳纳米管(N-MWCNTs)。合成N-MWCNTs的温度范围在750-875℃,氨气流速范围在100-450 mL/min。采用XPS、TEM、XRD、FT-IR和Raman等技术对制备的N-MWCNTs进行了表征。XPS研究表明,所合成的N-MWCNTs中有三种不同类型的氮,分别是吡啶型氮、石墨型氮和分子型氮。理论计算表明,N-MWCNTs中的吡啶型氮比石墨型氮更易于吸附NO分子。采用循环伏安(CV)和交流阻抗(EIS)法考察了NO在N-MWCNTs修饰电极上的电氧化活性。研究结果表明：所制备的N-MWCNTs,其氮掺杂含量和吡啶型氮含量,对NO的电氧化活性起到了至关重要的作用,即吡啶型氮含量越高,电氧化反应速率越快。因此,含较高吡啶型氮的N-MWCNTs是很好的电极材料,可以被用来检测和移除NO。对N-MWCNTs进行了NO气敏性研究。结果表明N-MWCNTs中氮含量和吡啶型氮含量的增加,能够提高N-MWCNTs对NO的敏感度。更多还原

【Abstract】 In this paper, nitrogen-doped multiwalled carbon nanotubes (N-MWCNTs) were synthesized by pyrolysis of pyridine and iron phthalocyanine over iron supported catalyst. Various N-MWCNTs with different N content were prepared using chemical vapor deposition method. The synthesis conditions were controlled in the temperature range 750-875℃, and in the NH3 flow rate range 100-450 mL/min.The samples were characterized by XPS, TEM, XRD, FT-IR and Raman. The XPS analysis results demonstrate that there are three types of N atoms in them, namely pyridine-like, graphite-like and molecular N. The theoretical calculation indicates that the pyridine-like N is easier than the graphite-like N to adsorb NO molecules.Cyclic voltammetry and electrochemical impedance spectroscopy were carried on for the study of NO electrooxidation on the N-MWCNTs modified electrodes. The measurement results indicate that the total doped N and the pyridine-like N of obtained N-MWCNTs play important roles in the electrooxidation of NO. The high content of pyridine-like N can increase the electrooxidation rate of NO. Therefore, N-MWCNTs with high pyridine-like N are the excellent electrode materials and can be used for detect and remove NO.The gas-sensing behavior of N-MWCNTs to NO was reported here. The test results indicate that the increase of total doped N and the pyridine-like N of N-MWCNTs can increase the sensitivity to NO gas.更多还原