An Electrochemical Model for Gold Colloid Formation via Citrate Reduction
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Benito Rodríguez-González
The mechanism of nanoparticle formation during the reduction of HAuCl4 with sodium citrate under reflux has been studied. We have found that the redox potential in the nucleating colloid remains very positive, around +0.75V vs. Ag/AgCl, until the reaction is almost complete. It then shifts suddenly to around +0.1V vs. Ag/AgCl at the end of the reaction, which is close to the final open-circuit potential in the sol. AuCl4- continues to be reduced slowly over the course of the reaction, but is suddenly depleted as the potential shifts near the end of the reaction. The change in potential is correlated to the peptization of aggregates to form the final monodisperse gold particles. There is also a blue-shift of the surface plasmon band associated with charging of the gold particles.
© Oldenbourg Wissenschaftsverlag
Articles in the same Issue
- Preface – Professor Dr. Arnim Henglein on the occasion of his 80th birthday
- Surface Chemistry of Semiconductor Nanocrystals
- Synthesis and Assembling of Semiconductor and Metal Nanocrystals
- The Electronic Role of the TiO2 Light-Scattering Layer in Dye-Sensitized Solar Cells
- Primary Processes During the Photodeposition of Ag Clusters on TiO2 Nanoparticles
- Photoactivity of Sol–Gel Derived Nitridated ZnxTiyOz-Films
- Photothermal Properties of Gold Nanoparticles
- Electro-Assisted Photo-Luminescence of Colloidal Germanium Nanoparticles
- Cobalt-Doped ZnO Nanorods Fabricated by a Simple Wet Chemical Route in Alcoholic Solution
- Influence of the Choice of Indium Precursor and Ligand on the Synthesis of InP Nanocrystals
- Formation of the Silver Hydride Ion AgH+ upon the Reduction of Silver Ions by H· in Aqueous Solution. A Pulse Radiolysis Study
- An Electrochemical Model for Gold Colloid Formation via Citrate Reduction
- Synthesis of Monodisperse PbS Nanoparticles and Their Assembly into Highly Ordered 3D Colloidal Crystals
Articles in the same Issue
- Preface – Professor Dr. Arnim Henglein on the occasion of his 80th birthday
- Surface Chemistry of Semiconductor Nanocrystals
- Synthesis and Assembling of Semiconductor and Metal Nanocrystals
- The Electronic Role of the TiO2 Light-Scattering Layer in Dye-Sensitized Solar Cells
- Primary Processes During the Photodeposition of Ag Clusters on TiO2 Nanoparticles
- Photoactivity of Sol–Gel Derived Nitridated ZnxTiyOz-Films
- Photothermal Properties of Gold Nanoparticles
- Electro-Assisted Photo-Luminescence of Colloidal Germanium Nanoparticles
- Cobalt-Doped ZnO Nanorods Fabricated by a Simple Wet Chemical Route in Alcoholic Solution
- Influence of the Choice of Indium Precursor and Ligand on the Synthesis of InP Nanocrystals
- Formation of the Silver Hydride Ion AgH+ upon the Reduction of Silver Ions by H· in Aqueous Solution. A Pulse Radiolysis Study
- An Electrochemical Model for Gold Colloid Formation via Citrate Reduction
- Synthesis of Monodisperse PbS Nanoparticles and Their Assembly into Highly Ordered 3D Colloidal Crystals
