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Abstract This paper presents a facile synthesis of Cu twin cubes, with a yield ofca. 70%, from seeds based on Pd hexagonal nanoplates. The lattice mismatch, capping agent, and number of planar defects in the seeds all play important roles in directing the shape evolution of Cu on the Pd seeds. Initially, the Cu atoms are only deposited on one of the two basal planes of a Pd nanoplate in the form of small islands. As the growth continues, Cu {100} facets developed in the presence of hexadecylamine and Cl−, two capping agents with selectivity towards the Cu(100) surface. When switched to Pd triangular nanoplates, Cu right bipyramids instead of cubes are obtained and only three {100} facets are created from each side of the seed. Atomic‐resolution transmission electron microscopy analysis indicates that the correspondence between the type of the seed and the shape of the final product can be attributed to the number of planar defects along the vertical direction of the plate‐like seed, with two and one twin planes corresponding to cube and right bipyramid, respectively. By adjusting the experimental condition, this synthetic method can also be extended to Pd−Ag and other bimetallic systems.
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Anisotropic Seeded Growth of Ag Nanoplates Confined in Shape‐Deformable Spaces
Abstract Conventional templating synthesis confines the growth of seeds in rigid spaces to achieve faithful morphological replication. Herein, we explore the use of spherical shape‐deformable polymeric nanoshells to regulate the anisotropic growth of Ag nanoplates. The flexible shells deform adaptively to accommodate the initial overgrowth of the seeds but restrict the growth in the directions where the shells are fully stretched, eventually producing nanoplates with an unconventional circular profile. The diameter of the final Ag nanoplates can be precisely predicted by stretching and flattering the nanoshells into a plate‐like capsule while retaining their original internal surface area. Furthermore, unlike conventional templates, the polymer shells eventually turn themselves into a conformal coating that binds to the surface of the full‐grown Ag nanoplates and significantly enhances their stability against oxidative etching.
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- Award ID(s):
- 1808788
- PAR ID:
- 10236099
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Angewandte Chemie International Edition
- Volume:
- 60
- Issue:
- 8
- ISSN:
- 1433-7851
- Page Range / eLocation ID:
- p. 4117-4124
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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