Nanocages comprise a novel class of nanostructures possessing hollow interiors and porous walls. They are prepared using a remarkably simple galvanic replacement reaction between solutions containing metal precursor salts and Ag nanostructures prepared through polyol reduction. The electrochemical potential difference between the two species drives the reaction, with the reduced metal depositing on the surface of the Ag nanostructure. In our most studied example, involving HAuCl4 as the metal precursor, the resultant Au is deposited epitaxially on the surface of the Ag nanocubes, adopting their underlying cubic form. Concurrent with this deposition, the interior Ag is oxidized and removed, together with alloying and dealloying, to produce hollow and, eventually, porous structures that we commonly refer to as Au nanocages. This approach is versatile, with a wide range of morphologies (e.g., nanorings, prism-shaped nanoboxes, nanotubes, and multiple-walled nanoshells or nanotubes) available upon changing the shape of the initial Ag template. In addition to Au-based structures, switching the metal salt precursors to Na2PtCl4 and Na2PdCl4 allows for the preparation of Pt- and Pd-containing hollow nanostructures, respectively.
Related Journals of Nanocages
Nano Research & Applications, Journal of Nanomedicine & Nanotechnology, Bioceramics Development and Applications, Materials Express, Journal of Micro-Nano Mechatronics, Microelectronics Journal, Journal of Micro/ Nanolithography, MEMS, and MOEMS, IET Nanobiotechnology, Nanoscience and Nanotechnology Letters