On the minimum reactant concentration required to prepare Au/M core-shell nanoparticles by the one-pot microemulsion route
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C. Tojo
C. Tojo is Professor of Physical Chemistry at the University of Vigo (Spain). She has published 56 publications with more than 900 citations (h-index 16). Her research fields include the synthesis of metallic and bimetallic particles in microemulsions, nanostructured bimetallic materials and chemical kinetics in microemulsions.
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D. Buceta
David Buceta defended his PhD in Chemistry in 2011 in the University of Santiago de Compostela (USC, Spain). He is currently a Postdoc of Physical Chemistry at same university. He was 3 years as a Postdoc in Germany, at the Technische Universität Berlin, working in photocatalysis. Before, he spent 3 years in USA, at the Brookhaven National Laboratory (NY), working in fuel cells and bimetallic particles. He has more than 25 papers with more than 450 citations (h-index 12). Youngest Scientific Advisor of the company NANOGAP (www.nanogap.es ), a spin-off from the USC founded in 2006 and dedicated to the production of nanomaterials and sub-nm metal (0) clusters. His research interests are the synthesis of metallic and bimetallic particles and their catalytic and electrocatalytic properties; synthesis of “ligand-free” subnanometric clusters and the study of their properties (for instance photocatalysis, electrocatalysis, heterogeneous and homogeneous catalysis and biomedical properties).M. Arturo López-Quintela is Full Professor of Physical Chemistry at the University of Santiago de Compostela (USC, Spain). Postdoc in Germany at MPI für Biophysikalishe Chemie, Göttingen and University of Bielefeld. Visiting Professor at MPI für Metallforschung, Stuttgart, Germany; Centre for Magnetic Recording Research, UCLA, USA; Yokohama Natl. University, Japan and Research Centre for Materials Science, Nagoya, Japan. Solvay Award in Chemistry and Burdinola Award in the Field of New Nanotechnologies in Chemistry. Co-founder and Principal Scientific Advisor of the company NANOGAP (www.nanogap.es ), a spin-off from the USC founded in 2006 and dedicated to the production of nanomaterials and sub-nm metal (0) clusters. Since 2005 Co-editor of the Journal of Colloid and Interface Science. He has published more than 300 publications (h-index 53) and is co-author of 26 patents (most of them under exploitation). His current research interests are synthesis and properties of nanomaterials and “ligand-free” metal clusters by soft chemical techniques; synthesis of anisotropic nanomaterials and nanocomposites; catalytic, electrocatalytic, photocatalytic and therapeutic properties of “ligand-free” clusters.
Abstract
The minimum reactant concentration required to synthesize Au/M (M = Ag, Pt, Pd, Ru …) core-shell nanoparticles by the one-pot microemulsion route was calculated by a simulation model under different synthesis conditions. This minimum concentration was proved to depend on the reduction potential of the slower metal M and on the rigidity of the surfactant film composing the microemulsion. Model results were tested by comparing with Au/M nanoparticles taken from literature. In all cases, experimental data obey model predictions. From this agreement, one can conclude that the smaller the standard potential of the slower reduction metal, the lower the minimum concentration needed to obtain core-shell nanoparticles. In addition, the higher the surfactant flexibility, the higher the minimum concentration to synthesize metal segregated nanoparticles. Model prediction allows to quantify which is the best value of concentration to prepare different pairs of core-shell Au/M nanoparticles in terms of nature of M metal in the couple and microemulsion composition. This outlook may become an advanced tool for fine-tuning Au/M nanostructures.
Graphical Abstract:
About the authors
C. Tojo is Professor of Physical Chemistry at the University of Vigo (Spain). She has published 56 publications with more than 900 citations (h-index 16). Her research fields include the synthesis of metallic and bimetallic particles in microemulsions, nanostructured bimetallic materials and chemical kinetics in microemulsions.
David Buceta defended his PhD in Chemistry in 2011 in the University of Santiago de Compostela (USC, Spain). He is currently a Postdoc of Physical Chemistry at same university. He was 3 years as a Postdoc in Germany, at the Technische Universität Berlin, working in photocatalysis. Before, he spent 3 years in USA, at the Brookhaven National Laboratory (NY), working in fuel cells and bimetallic particles. He has more than 25 papers with more than 450 citations (h-index 12). Youngest Scientific Advisor of the company NANOGAP (www.nanogap.es), a spin-off from the USC founded in 2006 and dedicated to the production of nanomaterials and sub-nm metal (0) clusters. His research interests are the synthesis of metallic and bimetallic particles and their catalytic and electrocatalytic properties; synthesis of “ligand-free” subnanometric clusters and the study of their properties (for instance photocatalysis, electrocatalysis, heterogeneous and homogeneous catalysis and biomedical properties).
M. Arturo López-Quintela is Full Professor of Physical Chemistry at the University of Santiago de Compostela (USC, Spain). Postdoc in Germany at MPI für Biophysikalishe Chemie, Göttingen and University of Bielefeld. Visiting Professor at MPI für Metallforschung, Stuttgart, Germany; Centre for Magnetic Recording Research, UCLA, USA; Yokohama Natl. University, Japan and Research Centre for Materials Science, Nagoya, Japan. Solvay Award in Chemistry and Burdinola Award in the Field of New Nanotechnologies in Chemistry. Co-founder and Principal Scientific Advisor of the company NANOGAP (www.nanogap.es), a spin-off from the USC founded in 2006 and dedicated to the production of nanomaterials and sub-nm metal (0) clusters. Since 2005 Co-editor of the Journal of Colloid and Interface Science. He has published more than 300 publications (h-index 53) and is co-author of 26 patents (most of them under exploitation). His current research interests are synthesis and properties of nanomaterials and “ligand-free” metal clusters by soft chemical techniques; synthesis of anisotropic nanomaterials and nanocomposites; catalytic, electrocatalytic, photocatalytic and therapeutic properties of “ligand-free” clusters.
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Articles in the same Issue
- Synergistic visible light photoredox catalysis
- On the minimum reactant concentration required to prepare Au/M core-shell nanoparticles by the one-pot microemulsion route
- Synthesis and characterization of graphene quantum dots
- Visible-light photoredox catalysis with [Ru(bpy)3]2+: General principles and the twentieth-century roots
- X-ray absorption spectroscopy principles and practical use in materials analysis
Articles in the same Issue
- Synergistic visible light photoredox catalysis
- On the minimum reactant concentration required to prepare Au/M core-shell nanoparticles by the one-pot microemulsion route
- Synthesis and characterization of graphene quantum dots
- Visible-light photoredox catalysis with [Ru(bpy)3]2+: General principles and the twentieth-century roots
- X-ray absorption spectroscopy principles and practical use in materials analysis
