Modification of carbon nanotube surfaces with precious metal and transition metal oxide nanoparticles using thin silica layers

作者：Takenaka Sakae^*; Mikami Daisuke; Tanabe Eishi; Matsune Hideki; Kishida Masahiro

来源：Applied Catalysis A: General , 2015, 492: 60-67.

DOI：10.1016/j.apcata.2014.12.025

• Carbon nanotube
• Silica layer
• Precious metal nanoparticle
• Transition metal oxide nanoparticle

The surfaces of carbon nanotubes (CNTs) were covered with thin silica layers through the application of 3-aminopropyltriethoxysilane (APTES) in order to enhance the deposition of precious metal and transition metal oxide nanoparticles. Pt metal particles smaller than 2nm in diameter could be deposited, using a conventional impregnation method, on CNTs coated with silica layers, whereas Pt particles supported on bare CNT surfaces were approximately 3 nm in diameter. Thus, coating CNTs with thin silica layers enhanced the catalytic activity of the Pt catalysts. In addition, CNTs with thin silica layers could be uniformly covered with transition metal oxide layers (ZrO2, Nb2O5 and Ta2O5) by hydrolysis of the corresponding metal alkoxides. In contrast, metal oxides were very difficult to deposit on bare CNTs. The thin silica layers produced on the CNTs via the use of APTES evidently function as adsorption sites for precursor metals and metal oxides, as well as nucleation sites for metals and metal oxides, allowing the formation of precious metal-CNT and transition metal oxide-CNT composites.

• 出版日期2015-2-25