Preparation of Carbon Nanotube-Supported Pt Metal Particles Covered with Silica Layers and Their Application to Electrocatalysts for PEMFC
Preparation of Carbon Nanotube-Supported Pt Metal Particles Covered with Silica Layers and Their Application to Electrocatalysts for PEMFC
复制标题
DOI：
10.1007/s11244-009-9207-3
复制
发表时间：
2009-04
影响因子：
3.6
通讯作者：
S. Takenaka;H. Matsumori;Takafumi Arike;H. Matsune;M. Kishida
中科院分区：
文献类型：
--
作者：
S. Takenaka;H. Matsumori;Takafumi Arike;H. Matsune;M. Kishida
通过水解3-氨丙基-三乙氧基硅烷（APTES）和/或四乙氧基硅烷（TEOS），在碳纳米管（CNT）负载的Pt金属纳米颗粒上覆盖二氧化硅层。仅APTES的水解导致二氧化硅层在Pt/CNT上的均匀覆盖，但二氧化硅层的厚度非常薄（<lnm）。Pt/CNT也可以通过TEOS的水解涂覆几个纳米厚的二氧化硅层，但是经常观察到样品中暴露的CNT表面。相比之下，APTES和TEOS的连续水解导致Pt/CNT上几纳米厚的二氧化硅层的均匀覆盖。SiO2包覆的Pt/CNT对H2SO 4水溶液电解液中的电化学反应表现出较高的催化活性，尽管Pt金属被SiO2层均匀覆盖。此外，用二氧化硅层覆盖Pt/CNT提高了其在电化学反应中的耐久性。
Carbon nanotube (CNT)-supported Pt metal nanoparticles were covered with silica layers by hydrolysis of 3-aminopropyl-triethoxysilane (APTES) and/or tetraethoxysilane (TEOS). The hydrolysis of only APTES resulted in a uniform coverage of silica layers on Pt/CNT, but the thickness of the silica layers was very thin (<1 nm). Pt/CNT could also be coated with silica layers of a few nanometers in thickness by hydrolysis of TEOS, but exposed surfaces of CNTs in the sample were frequently observed. In contrast, the successive hydrolysis of APTES and TEOS brought about a uniform coverage of silica layers of a few nanometers in thickness on Pt/CNT. The silica-coated Pt/CNT showed high catalytic activity for electrochemical reactions in aqueous H2SO4electrolyte, in spite of a uniform coverage of Pt metal with silica layers. In addition, the coverage of Pt/CNT with silica layers improved its durability in electrochemical reactions.