Papers by Author: Heng Yi Su

Abstract: Carbon nanotubes (CNTs) were functionalized using a simple method of heat treatment under oxygen atmosphere followed by an immersion in a tin nitrate aqueous solution. And well-dispersed SnOx nanodots were decorated on the surface of CNTs. X-ray photoelectron spectroscopy (XPS) analysis showed that the O/C ratio increases with oxygen-treated time. The distribution of carbon-containing functional groups on the CNTs surface, i.e., C−C, C−O, C=O, O−C=O, and π−π* shake up bonds can be identified and deconvoluted by a symmetrical Gauss function. The contact angle of H2O and CNTs is dependent on O/C ration. The relationships between the fraction of carbon-containing functional groups and various oxygen treatment times are also discussed.

Abstract: Through self-assembly monolayer surface treatment, metal oxide nanoparticles uniformly dispersed onto carbon nanotubes (CNTs) surface are investigated. At first, oxidation treatment was performed to increase O/C ratio of CNTs surface at 250°C for 1 hr under an oxygen atmosphere. X-ray photoelectron spectroscopy (XPS) analysis shows that O/C ratio is a increasing function of oxidating time. Distribution of oxygen functional groups on CNTs surface, i.e., carboxyl, carbonyl, phenolic groups, can be identified and deconvoluted by a symmetrical Gauss function. Experiments indicate that heat time for 5hr can produce a greater O/C ratio on CNTs surface. It is observed that carboxyl groups acts an important role to link with metal ions via an ionic interaction, thus, forming a monolayer adsorption on CNTs surface. By heating the treated CNTs, a completely composite nanostructure is thus formed. In the present work, we successfully fabricate three kinds of nanoparticles including SnO2, and RuO2, with an average diameter of 5-10 nm coated on the CNTs.