Fine-tuning the shape of gold nanorods
Fine-tuning the shape of gold nanorods
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DOI：
10.1021/cm050525w
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发表时间：
2005-07-12
影响因子：
8.6
通讯作者：
Murphy, CJ
中科院分区：
文献类型：
--
作者：
Gou, LF;Murphy, CJ
通过种子介导生长方法制备的金纳米棒使用类似于4纳米的金纳米球作为种子，随后使用弱还原剂（抗坏血酸）在指导表面活性剂存在下还原金属盐以产生纳米棒。如果在生长阶段添加的抗坏血酸不足，那么金属盐就会残留。额外的抗坏血酸会优先在纳米棒的末端沉积更多的金属，从而产生“狗骨”状结构。令人惊讶的是，热处理未纯化的金纳米棒（用不足量的抗坏血酸制备）会产生更肥的金纳米棒；抗坏血酸的氧化产物在较高温度下似乎起还原剂的作用。金纳米棒的这些修饰形状直接影响了它们的光学性质。
Gold nanorods prepared by a seed-mediated growth approach use similar to 4-nm gold nanospheres as the seeds and subsequent reduction of metal salt with a weak reducing agent (ascorbic acid) in the presence of a directing surfactant to produce nanorods. If insufficient ascorbic acid is added in the growth step, then metal salt remains. Additional input of ascorbic acid preferentially deposits more metal at the ends of the nanorods, to yield "dogbone"- like structures. Surprisingly, heat treatment of the unpurified gold nanorods (prepared with an insufficient amount of ascorbic acid) yielded fatter gold nanorods; the oxidation product of ascorbic acid appears to act as a reductant at higher temperature. These modified shapes of the gold nanorods directly influence their optical properties.