Study of the surface chemistry of modified carbon nanofibers by oxidation treatments in liquid phase.
Study of the surface chemistry of modified carbon nanofibers by oxidation treatments in liquid phase.
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液相氧化处理改性碳纳米纤维的表面化学研究。
DOI：
10.1166/jnn.2009.m26
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发表时间：
2009
影响因子：
--
通讯作者：
R. Moliner
中科院分区：
文献类型：
--
作者：
L. Calvillo;M. Lázaro;I. Suelves;Y. Echegoyen;E. G. Bordejé;R. Moliner
采用甲烷热催化分解法制备了碳纳米纤维。通过用不同浓度的HNO 3或HNO 3-H2SO 4的混合物进行不同的氧化处理来改性它们的纹理和表面化学，以优化它们分散活性金属颗粒的能力，因为这种材料将用作聚合物电解质燃料电池的电催化载体。采用程序升温脱附（TPD）、扫描电镜（SEM）和N2-物理吸附等方法研究了液相氧化对CNF表面化学和织构性质的影响。此外，通过程序升温氧化（TPO）研究了它们的热稳定性。在氧化处理过程中产生官能团，并且它们的数量是氧化处理条件的函数。结果表明，氧化处理程度的增加会导致表面氧基团数量的增加和热稳定性的增加。然而，非常严厉的处理可能会部分破坏碳纳米纤维的结构。
Carbon nanofibers (CNF) were grown by thermocatalytic decomposition of methane. Their texture and surface chemistry were modified by different oxidation treatments with HNO3 at different concentrations or a mixture of HNO3-H2SO4 to optimise their ability of dispersing active metal particles, because this material will be used as electrocatalytic support for polymeric electrolyte fuel cells. The effect of liquid phase oxidation on the surface chemistry and the textural properties of the CNF was studied by temperature programmed desorption (TPD), scanning electron microscopy (SEM) and N2-physisorption. Moreover, their thermal stability was studied by temperature programmed oxidation (TPO). During oxidation treatments functional groups were created and their number was function of the oxidation treatment conditions. Results indicated that an increase in severity of the oxidation treatment produces an increase in the number of surface oxygen groups and in the thermal stability. However, a very severe treatment can destroy partially the structure of carbon nanofibers.