Zur Kenntnis der Amalgame, II

Paal, C.; Steyer, Hermann

doi:10.1007/bf01427361

Cited by 4 publications

(9 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

Section: Resultsmentioning

confidence: 97%

“…Size statistical measurements also showed that the volume of as-deposited nanorods was on average 20 000 nm 3 . However, at the end of the reshaping process (10 mM Hg) the average nanorod volume increased to 38 000 nm 3 , corresponding to an increase in volume of 90% and a calculated average Hg content of 38 at%. In order to demonstrate that the observed volume increase was associated to the incorporation of Hg into the metal structure, EDX analysis was performed of deposited nanorods exposed to 5 mM Hg solution (see Fig.…”

Section: Resultsmentioning

confidence: 97%

“…Nanoscale amalgams have been prepared since the early days of colloid science by mixing Au and Hg hydrosols or by shaking Au sols in contact with liquid Hg for a long time. [1][2][3] In the last ten years there has been renewed interest for this research field, propelled by the recent advances in nano-synthesis, which have made metal nanoparticles of desired shape, composition and narrow size distribution readily available. [4][5][6] The potential of Au-Hg nanocomposites for novel applications such as sensing and environmental analysis has been recently demonstrated.…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Investigation of Au–Hg amalgam formation on substrate-immobilized individual Au nanorods

et al. 2015

View full text Add to dashboard Cite

Electronic Supplementary Information (ESI) available: . Influence of NaBH4 and Hg(II) exposure on Au nanorod optical properties, SEM images and statistical size analysis of nanorods exposed to Hg(II) solutions, detailed EDX analysis, theoretical calculations. SeeIn this work we investigated the process of Au-Hg alloy formation occurring on individual substrate-immobilized Au nanorods exposed to Hg(II) solutions. Dramatic transitions in the light scattered by nanorods from red to yellow or even green color and remarkable blue shifts in the corresponding scattering spectra were detected upon chemical reduction of Hg(II). Such changes occurred as result of amalgam formation and were correlated to deposition of Hg on nanorod surfaces and subsequent reduction of the nanorods' aspect ratio towards a spherical shape. Theoretical calculations were used to support experimental findings. Time-dependent monitoring of optical changes occurring to substrate-immobilized nanorods during exposure to Hg(II) solutions and during their subsequent exposure to air were also performed. Finally a mechanism for Au-Hg amalgamation was proposed where initial fast deposition of Hg on nanorod surfaces was followed by slow diffusion of Hg into the nanorod lattices.Investigation of controlled amalgamation of gold nanorods with chemically reduced mercury in aqueous solution leading to dramatic optical and morphological changes in the nanorods.

show abstract

Section: Resultsmentioning

confidence: 97%

Section: Resultsmentioning

confidence: 97%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Investigation of Au–Hg amalgam formation on substrate-immobilized individual Au nanorods

et al. 2015

View full text Add to dashboard Cite

show abstract

“…Using method I (fast stirring), the concentration of mercury increases and that of gold decreases linearly with time corresponding to overall zero‐order Hg incorporation reaction kinetics. In the absence of Au nanoparticles, no free Hg colloid formation is observed 12, 13…”

Section: Resultsmentioning

confidence: 99%

“…In this paper, we demonstrate that direct amalgamation of a gold hydrosol, removing the need of mercury ion reduction, allows precise tuning of the resulting Au@Hg nanoparticle composition as simple zero‐order kinetics are encountered. The method is based on early work by Paal and Steyer,12, 13 whose clusters, however, were to our knowledge never fully characterized. In addition, we present the first comprehensive study of the nanoalloy formation, combining structural characterization (transmission electron microscopy, X‐ray powder diffraction and optical absorption spectroscopy) and theoretical calculations (discrete dipole approximation (DDA) and density functional theory (DFT)).…”

Section: Introductionmentioning

confidence: 99%

Au@Hg Nanoalloy Formation Through Direct Amalgamation: Structural, Spectroscopic, and Computational Evidence for Slow Nanoscale Diffusion

Mertens

Gara

Sologubenko

et al. 2011

Adv Funct Materials

View full text Add to dashboard Cite

Dynamic core–shell nanoparticles have received increasing attention in recent years. This paper presents a detailed study of Au–Hg nanoalloys, whose composing elements show a large difference in cohesive energy. A simple method to prepare Au@Hg particles with precise control over the composition up to 15 atom% mercury is introduced, based on reacting a citrate stabilized gold sol with elemental mercury. Transmission electron microscopy shows an increase of particle size with increasing mercury content and, together with X‐ray powder diffraction, points towards the presence of a core–shell structure with a gold core surrounded by an Au–Hg solid solution layer. The amalgamation process is described by pseudo‐zero‐order reaction kinetics, which indicates slow dissolution of mercury in water as the rate determining step, followed by fast scavenging by nanoparticles in solution. Once adsorbed at the surface, slow diffusion of Hg into the particle lattice occurs, to a depth of ca. 3 nm, independent of Hg concentration. Discrete dipole approximation calculations relate the UV–vis spectra to the microscopic details of the nanoalloy structure. Segregation energies and metal distribution in the nanoalloys were modeled by density functional theory calculations. The results indicate slow metal interdiffusion at the nanoscale, which has important implications for synthetic methods aimed at core–shell particles.

show abstract

Absorption Spectra and Reactions of Colloidal Bimetallic Nanoparticles Containing Mercury

1997

View full text Add to dashboard Cite

Silver and mercury ions are reduced in a common solution by sodium borohydride in the presence of poly(ethyleneimine). Colloidal alloy particles are formed, whose plasmon absorption band is blue-shifted with increasing mercury-to-silver ratio. The reduction mechanism is rather complex: large mercury "drops" are first formed, although silver ions are reduced simultaneously. This effect is explained by an interaction of the two metal redox systems, as silver clusters are reoxidized by mercury ions. The final particles are formed in a reaction of the mercury drops with reduced silver clusters, yielding amalgam particles smaller than the mercury drops. These processes are followed by spectrophotometric and light-scattering measurements. The alloy colloids are stable up to a mercury to silver molar ratio of 2. Upon exposure to air, part of the mercury in the alloy particles is oxidized.

show abstract

Zur Kenntnis der Amalgame, II

Cited by 4 publications

References 0 publications

Investigation of Au–Hg amalgam formation on substrate-immobilized individual Au nanorods

Investigation of Au–Hg amalgam formation on substrate-immobilized individual Au nanorods

Au@Hg Nanoalloy Formation Through Direct Amalgamation: Structural, Spectroscopic, and Computational Evidence for Slow Nanoscale Diffusion

Absorption Spectra and Reactions of Colloidal Bimetallic Nanoparticles Containing Mercury

Contact Info

Product

Resources

About