Skip to Main content Skip to Navigation
Theses

Reactivity of nanoparticles at charged interfaces:
Electronic transfer in colloidal suspension and electrokinetic phenomena at the nanometric scale.

Abstract : The synthesis of a liquid displaying both magnetic properties and electronic conduction is possible by dispersing electrochemically and at room temperature iron nanoparticles in liquid metals (mercury and gallium) starting from iron oxide nanocolloidal particles. However, the mechanisms involved in the electrochemical transformation of charged thousand-atom particles are poorly known. For that purpose, the nanoparticules are described as electroactive ionic species by considering first the approach of the charged particles near charged surfaces and then the electron transfer between the particle and the electrode. The understanding of the charging and discharging mechanisms of the particles depending on the experimental conditions of pH, ionic strength and volume fraction is a necessary step in the study of the approach. This was achieved by coupling titration experiments, electrokinetic methods and suitable theoretical tools. Then, the association of atomic force microscopy, with optical techniques (reflectometry) and electrochemical measurements, carried out on solid metal substrates of very low roughness, enabled us to interpret the results obtained on liquid electrodes (mercury). Finally the detailed study of the electrochemical transformations showed that under suitable conditions, the particles keep size and shape properties after they underwent the electrochemical reaction, thereby justifying their use in the preparation of a conducting magnetic liquid.
Document type :
Theses
Complete list of metadata

Cited literature [71 references]  Display  Hide  Download

https://tel.archives-ouvertes.fr/tel-00200446
Contributor : Ivan T. Lucas <>
Submitted on : Thursday, December 20, 2007 - 7:14:19 PM
Last modification on : Wednesday, December 9, 2020 - 3:12:47 PM
Long-term archiving on: : Monday, April 12, 2010 - 8:43:23 AM

Identifiers

  • HAL Id : tel-00200446, version 1

Citation

Ivan Lucas. Reactivity of nanoparticles at charged interfaces:
Electronic transfer in colloidal suspension and electrokinetic phenomena at the nanometric scale.. Other. Université Pierre et Marie Curie - Paris VI, 2007. English. ⟨tel-00200446⟩

Share

Metrics

Record views

500

Files downloads

2556