Decoupling Mechanisms of Platinum Deposition on Colloidal Gold Nanoparticle Substrates

详细信息    查看全文

• 作者：Patrick J. Straney ; Lauren E. Marbella ; Christopher M. Andolina ; Noel T. Nuhfer ; Jill E. Millstone
• 刊名：Journal of the American Chemical Society
• 出版年：2014
• 出版时间：June 4, 2014
• 年：2014
• 卷：136
• 期：22
• 页码：7873-7876
• 全文大小：302K
• 年卷期：v.136,no.22(June 4, 2014)
• ISSN：1520-5126

文摘

Nanoscale platinum materials are essential components in many technologies, including catalytic converters and fuel cells. Combining Pt with other metals can enhance its performance and/or decrease the cost of the technology, and a wide range of strategies have been developed to capitalize on these advantages. However, wet chemical synthesis of Pt-containing nanoparticles (NPs) is challenging due to the diverse metal segregation and metal鈥搈etal redox processes possible under closely related experimental conditions. Here, we elucidate the relationship between Pt(IV) speciation and the formation of well-known NP motifs, including frame-like and core鈥搒hell morphologies, in Au鈥揚t systems. We leverage insights gained from these studies to induce a controlled transition from redox- to surface chemistry-mediated growth pathways, resulting in the formation of Pt NPs in epitaxial contact and linear alignment along a gold nanoprism substrate. Mechanistic investigations using a combination of electron microscopy and ¹⁹⁵Pt NMR spectroscopy identify Pt(IV) speciation as a crucial parameter for understanding and controlling the formation of Pt-containing NPs. Combined, these findings point toward fully bottom-up methods for deposition and organization of NPs on colloidal plasmonic substrates.