Department of Biomedical Engineering, Washington University, St. Louis, Missouri 63130, USA.
J Am Chem Soc. 2010 Mar 3;132(8):2506-7. doi: 10.1021/ja909787h.
This paper describes the synthesis of Pd-Au bimetallic nanocrystals with controlled morphologies via a one-step seeded-growth method. Two different reducing agents, namely, L-ascorbic acid and citric acid, were utilized for the reduction of HAuCl(4) in an aqueous solution to control the overgrowth of Au on cubic Pd seeds. When L-ascorbic acid was used as the reducing agent, conformal overgrowth of Au on the Pd nanocubes led to the formation of Pd-Au nanocrystals with a core-shell structure. On the contrary, localized overgrowth of Au was observed when citric acid was used as the reducing agent, producing Pd-Au bimetallic dimers. Through this morphological control, we were able to tune the localized surface plasmon resonance peaks of Pd-Au bimetallic nanostructures in the visible region.
本文通过一步种子生长法描述了具有可控形态的 Pd-Au 双金属纳米晶体的合成。两种不同的还原剂，即抗坏血酸和柠檬酸，被用于在水溶液中还原 HAuCl(4)，以控制 Au 在立方 Pd 种子上的过度生长。当使用抗坏血酸作为还原剂时，Au 在 Pd 纳米立方体上的共形过度生长导致形成具有核壳结构的 Pd-Au 纳米晶体。相反，当使用柠檬酸作为还原剂时，观察到 Au 的局部过度生长，生成 Pd-Au 双金属二聚体。通过这种形态控制，我们能够在可见区域调整 Pd-Au 双金属纳米结构的局域表面等离子体共振峰。
