Size-dependent transformation from Ag templates to Au–Ag nanoshells via galvanic replacement reaction in organic medium

Karvianto,; Chow, Gan Moog

doi:10.1007/s11051-012-1186-9

Cited by 13 publications

(6 citation statements)

References 67 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…However, application of this process in organic media has been restricted to spherical Ag nanoparticles, mainly due to the limitations in the synthesis of shape controlled Ag nanoparticles in these solvents. [42][43][44] We evaluated the application of the galvanic replacement reaction to our Ag nanocubes in a non-polar environment, at different reaction temperatures. Shown in Fig.…”

Section: Galvanic Replacement and Formation Of Au Nanocagesmentioning

confidence: 99%

Growth and galvanic replacement of silver nanocubes in organic media

Polavarapu

Liz‐Marzán

2013

Nanoscale

View full text Add to dashboard Cite

Although metal nanoparticles with various shapes can be prepared in polar organic solvents, little has been advanced toward the shape-controlled synthesis in non-polar solvents. We report a simple method for the synthesis of nearly monodisperse single crystalline silver nanocubes in a non-polar solvent (1,2-dichlorobenzene) by using oleylamine as both a reducing and capping agent. Mechanistic studies based on the time evolution of Ag nanoparticles revealed that multiply twinned nanocrystals form at the beginning of the reaction, which are gradually transformed into single crystalline Ag nanocubes by oxidative etching. Control experiments showed that the solvent plays an important role in the formation of such single crystalline Ag nanocubes. The effects of reaction temperature, oleylamine concentration, solvent, and the nature of the silver ion precursor on the morphology and monodispersity of the nanoparticles were systematically investigated. Additionally, the galvanic replacement reaction with HAuCl4 in an organic medium was implemented to prepare hydrophobic hollow Au-Ag nanocages with tunable localized surface plasmon resonances.

show abstract

Section: Galvanic Replacement and Formation Of Au Nanocagesmentioning

confidence: 99%

Growth and galvanic replacement of silver nanocubes in organic media

Polavarapu

Liz‐Marzán

2013

Nanoscale

View full text Add to dashboard Cite

show abstract

“…19 Galvanic replacement of 40 nm decahedra and 50 nm triangular prisms produced hollow alloys and preserved the shape of the Ag template. 20 Hong et al 21 showed that 40 nm single crystal spherical Ag NPs transformed into Au 30 Ag 70 octahedral nanoframes in the presence of CuCl, however their procedure using 20 nm NPs did not produce hollow structures but solid octahedra. Recent studies on galvanic replacement of 24 nm cubic NPs showed the Ag template transformed to an octahedral geometry.…”

Section: Introductionmentioning

confidence: 99%

Controlling alloy formation and optical properties by galvanic replacement of sub-20 nm silver nanoparticles in organic media

2015

View full text Add to dashboard Cite

show abstract

“…Core–shell nanocrystal (NC) synthesis is a field of immense recent progress on metal, semiconductor, or oxide NCs with techniques such as cation exchange − and seeded growth. − The galvanic replacement reaction (GRR) is a unique postsynthetic technique suited to produce bimetallic NCs. − Bimetallic NCs can exhibit complex nanostructures such as asymmetry , or Kirkendall voids − due to their complex energy landscape. The scaling laws of thermodynamic and kinetic properties governing nanoscale galvanic replacement reactions can vary significantly compared to reactions in the bulk phase . Quantitative understanding of the interplay between the thermodynamics and kinetic terms is essential for achieving the controlled synthesis of precise bimetallic core–shell NCs.…”

mentioning

confidence: 99%

Self-Limiting Shell Formation in Cu@Ag Core–Shell Nanocrystals during Galvanic Replacement

Kamat

Yan

Osowiecki

et al. 2020

J. Phys. Chem. Lett.

View full text Add to dashboard Cite

The understanding of synthetic pathways of bimetallic nanocrystals remains limited due to the complex energy landscapes and dynamics involved. In this work, we investigate the formation of self-limiting Cu@Ag core–shell nanoparticles starting from Cu nanocrystals followed by galvanic replacement with Ag ions. Bulk quantification with atomic emission spectroscopy and spatially resolved elemental mapping with electron microscopy reveal distinct nucleation regimes that produce nanoparticles with a tunable Ag shell thickness, but only up to a certain limiting thickness. We develop a quantitative transport model that explains this observed self-limiting structure as arising from the balance between entropy-driven interdiffusion and a positive mixing enthalpy. The proposed model depends only on the intrinsic physical properties of the system such as diffusivity and mixing energy and directly yields a high level of agreement with the elemental mapping profiles without requiring additional fit parameters.

show abstract

Size-dependent transformation from Ag templates to Au–Ag nanoshells via galvanic replacement reaction in organic medium

Cited by 13 publications

References 67 publications

Growth and galvanic replacement of silver nanocubes in organic media

Growth and galvanic replacement of silver nanocubes in organic media

Controlling alloy formation and optical properties by galvanic replacement of sub-20 nm silver nanoparticles in organic media

Self-Limiting Shell Formation in Cu@Ag Core–Shell Nanocrystals during Galvanic Replacement

Contact Info

Product

Resources

About