酸碱度对金纳米结构形貌的调控及其机理研究

摘要

We present a simple in situ synthesis method for preparing gold nanoparticles (Au NPs), in which the Au NPs self-aggregate into different microscale structures on a polyelectrolyte film (PEF) surface. In this approach, the aggregation behavior of Au NPs has been controlled by tuning the pH of the PEF, resulting in the different binding regime of the amine group. The round platelet gold structure has been observed on the surface of PEF with pH of 5. 40. The size of the dendritic structure obtained on the surface of acidic PEF with pH of 0. 65 is twice larger than that of the pH 5.40 PEF. In addition, the morphology of the gold structures changed into spheres when the pH changed from 5.40 to 12.77. Furthermore, the controlling mechanism of PEF has also been discussed.%本文通过调节环境pH酸碱度改变聚电解质膜中氨基基团的键合状态,以控制聚电解质膜表面金纳米粒子的原位还原与自组装过程中的聚集行为,发现当聚电解质膜经pH为5.40的去离子水处理后可在其表面制备出片状金纳米结构;经pH为0.65的强酸溶液处理后,可在膜表面制备出树枝状的金纳米结构,且尺寸比pH为5.40条件下增大一倍;经pH为12.77的强碱溶液处理后,金纳米粒子的聚集状态发生改变,形成了球形纳米结构;对金纳米粒子形貌的调控机理进行了初步探讨.