Understanding the role of shape-directing substances is crucial for the controllable preparation of anisotropic nanostructures through solution growths. Herein, we report a comparative investigation about the morphologies and structures of Au nanoparticles (Au NPs) synthesized using two different capping agents (hexadecyltrimethylammonium chloride (CTAC) and polyvinylpyrrolidone (PVP)) with/without the addition of iodide salts. The study manifests a synergistic effect of shape-directing agents on the growth pathways and shape formation. Depending on the specific use of surfactants/polymers, the iodide additives can promote the growth of prismatic anisotropic nanoparticles or lead to the shape evolution from irregular to quasi-spherical configurations.

中文翻译：

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形状导向剂对各向异性金纳米粒子形成的影响

了解形状导向物质的作用对于通过溶液生长可控制备各向异性纳米结构至关重要。在此，我们报告了使用两种不同的封端剂（十六烷基三甲基氯化铵 (CTAC) 和聚乙烯吡咯烷酮 (PVP)）合成的金纳米颗粒 (Au NPs) 的形态和结构的比较研究，其中添加/不添加碘化物盐。该研究显示了形状导向剂对生长途径和形状形成的协同作用。根据表面活性剂/聚合物的具体用途，碘化物添加剂可以促进棱柱形各向异性纳米颗粒的生长或导致形状从不规则结构演变为准球形结构。