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ChemInform Abstract: 25th Anniversary Article: Galvanic Replacement: A Simple and Versatile Route to Hollow Nanostructures with Tunable and Well-Controlled Properties

The Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, Georgia, 30332, USA.
Advanced Materials (Impact Factor: 17.49). 01/2014; 25(44). DOI: 10.1002/adma.201302820
Source: PubMed

ABSTRACT

This article provides a progress report on the use of galvanic replacement for generating complex hollow nanostructures with tunable and well-controlled properties. We begin with a brief account of the mechanistic understanding of galvanic replacement, specifically focused on its ability to engineer the properties of metal nanostructures in terms of size, composition, structure, shape, and morphology. We then discuss a number of important concepts involved in galvanic replacement, including the facet selectivity involved in the dissolution and deposition of metals, the impacts of alloying and dealloying on the structure and morphology of the final products, and methods for promoting or preventing a galvanic replacement reaction. We also illustrate how the capability of galvanic replacement can be enhanced to fabricate nanomaterials with complex structures and/or compositions by coupling with other processes such as co-reduction and the Kirkendall effect. Finally, we highlight the use of such novel metal nanostructures fabricated via galvanic replacement for applications ranging from catalysis to plasmonics and biomedical research, and conclude with remarks on prospective future directions.

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    • "Recent investigations have shown that Te nanowires are versatile templates for obtaining 1D metallic structures due to ease of their synthesis, usability across a number of solvents unlike the soft templates as well as favorable reduction potential to undergo galvanic displacement (GD) by many catalytically active metals [35] [36]. For instance, Liang et al. and Li et al. reported facile synthesis of Pt and PtPdTe nanowires using Te NW as template [12] [35]. "
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    • "At this point the structure has also developed a single large opening at its base. This is followed by a progression which transforms the structure into a nanocage [1], a designation attributed to hollow structures with a geometric pattern of openings over their surface (Figs. 2(g) and 2(h)). "
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