【作者】 杨烽； 王晓； 张达奇； 杨娟； 李彦；

【Author】 Feng Yang;Xiao Wang;Daqi Zhang;Juan Yang;Yan Li;College of Chemistry and Molecular Engineering,Peking University;

【机构】 北京大学化学与分子工程学院；

【摘要】 单壁碳纳米管(SWNTs)由于具有丰富的能带结构、优异的性质而成为近年来最受关注的材料之一。直接可控生长得到单一手性(n,m)SWNTs目前仍然是一个巨大挑战[1],文献报道最高的单一手性含量仅有55%。我们首次发展了一种新型的钨基双金属合金纳米催化剂,生长得到了单一手性选择性高于92%的(12,6)SWNT。这类催化剂具有很高的熔点,在碳管生长过程中可以保持固态、晶化的稳定结构。实验和理论模拟都表明高选择性生长(12,6)-SWNTs是由于SWNT末端碳原子结构与合金催化剂特定晶面结构具有非常好的匹配,并且合金纳米催化剂晶面具有特殊的原子排列[2]。利用这种具有特定晶面结构的固体合金催化剂为精确可控生长单一手性SWNTs提供了一条全新的思路。更多还原

【Abstract】 Structurally uniform and chirality-pure single-wall carbon nanotubes(SWNTs) are highly desired for both fundamental study and many of their technological applications. The ultimate goal of producing just one type of SWNT by controlling its structure during growth has proved to be a considerable challenge over the last two decades. Here we show that SWNTs of a single chirality,(12,6), can be produced directly with an abundance higher than 92% when using as catalysts tungsten-based bimetallic alloy nanocrystals that have such high melting points that they maintain their crystalline structure during the CVD process. This feature seems crucial because experiment and simulation both suggest that the highly selective growth of(12,6) SWNTs is the result of a good structural match between the carbon atom arrangement around the nanotube circumference and the arrangement of the catalytically active atoms in one of the planes of the nanocrystal catalyst.更多还原