金纳米棒的生长及与FeCl_3的作用

采用三氯化铁选择性刻蚀法获得了预定长径比的金纳米棒.相比于晶种生长法,三氯化铁选择性刻蚀法可以更加简便快捷地调控金纳米棒形貌.以三氯化铁为刻蚀剂的刻蚀反应优先发生在金纳米棒尖端,这是因为金纳米棒尖端反应活性更高且表面活性剂钝化作用更弱.通过控制刻蚀反应时间及刻蚀剂浓度,可以精确调控金纳米棒的长径比.实验结果表明,增加刻蚀剂浓度、卤素离子浓度以及升高反应温度可以加快刻蚀反应速率.进一步讨论了金属离子的刻蚀作用机理.

Growth of Gold Nanorods and Their Interaction with Ferric Chloride

Gold nanorods(AuNRs) with predetermined aspect ratios were obtained by the ferric chloride(FeCl3) selective etching method.Compared with the seed growth method, the FeCl3 selective etching method is simpler and faster.The etching reaction takes place preferentially at the tip of gold nanorods due to the higher reaction activity and the less surface passivation at the tips of the gold nanorod.By controlling the reaction time and the concentration of the etchant, the aspect ratio of the gold nanorods can be precisely controlled.The experimental results show that the reaction rate increased by increasing the concentrations of the etchant and the halide ion and the reaction temperature.The mechanism of metal ion etching was also disscussed.