Synthesis of Nanocrystals with Variable High-Index Pd Facets through the Controlled Heteroepitaxial Growth of Trisoctahedral Au Templates

Citations Over TimeTop 1% of 2010 papers

Abstract

The shape-controlled synthesis of noble metal nanocrystals (NCs) bounded by high-index facets is a current research interest because the products have the potential of significantly improving the catalytic performance of NCs in industrially important reactions. This study reports a versatile method for synthesizing polyhedral NCs enclosed by a variety of high-index Pd facets. The method is based on the heteroepitaxial growth of Pd layers on concave trisoctahedral (TOH) gold NC seeds under careful control of the growth kinetics. Polyhedral Au@Pd NCs with three different classes of high-index facets, including concave TOH NCs with {hhl} facets, concave hexoctahedral (HOH) NCs with {hkl} facets, and tetrahexahedral (THH) NCs with {hk0} facets, can be formed in high yield. The Miller indices of NCs are also modifiable, and we have used the THH NCs as a demonstrative example. The catalytic activities of these NCs were evaluated by the structure-sensitive reaction of formic acid electro-oxidation. The results showed that the high-index facets are generally more active than the low-index facets. In summary, a seeded growth process based on concave high-index faceted monometallic TOH NC templates and careful control of the growth kinetics is a simple and effective strategy for the synthesis of noble metal NCs with high-index facets. It also offers tailorability of the surface structure in shape-controlled synthesis.

Related Papers

• → Template routes to interlocked molecular structures and orderly molecular entanglements(2000)376 cited
• → Simultaneous control of nanocrystal size and nanocrystal-nanocrystal separation in CdS nanocrystal assembly(2005)55 cited
• → Manipulating the Charging Energy of Nanocrystal Arrays(2005)37 cited
• Hierarchical mechanical behavior of cobalt supracrystals related to nanocrystallinity(2015)
• → Writing Generic Code with Templates(2018)