Electrochemical Properties of Silver Nanoparticles in Mesoporous Silica and Titania Films: Specific Behavior of Titania Composite.

Electrochemical behavior of silver nanoparticles in mesoporous oxides electrodes is investigated. Mesoporous SiO and TiO films deposited on FTO (fluorine-doped tin oxide) and containing Ag nanoparticles (NPs) are used as electrodes. The study of voltammetric curves (CVs) and the diffusion of Ag ions out of the films highlight the importance of the retention of Ag ions by the TiO films.

Two-liquid wetting and phase electrowetting as a probe for surface chemistry of hydrophobic materials.

Two-liquid contact angle measurement and electrowetting under low frequency are two measurement methods extremely sensitive to surface polarity and charge density. The theory underlying these two methods are described and have been applied to hydrophobic coatings. By combining these two methods, we successfully demonstrated the variations of the surface properties of polymer-based hydrophobic coatings when exposed to different chemical environments (pH modification or molecular grafting) with real-time phase electrowetting measurements.

Electroactive Area from Porous Oxide Films Loaded with Silver Nanoparticles: Electrochemical and Electron Tomography Observations.

Electrochemical studies of nanomaterial-based electrodes have been widely developed for catalyst and energy-harvesting applications. The evolution of these electrodes over time and their efficiency have been extensively studied and analyzed in order to optimize their performance. However, the electrochemical responses of electrodes are rarely studied in terms of the position of the active species within these electrodes.

Photoelectrochemical Behavior of Silver Nanoparticles inside Mesoporous Titania: Plasmon-Induced Charge Separation Effect.

The self-assembly block copolymer method was used to synthesize mesoporous titania films and silver nanoparticles (NPs) were grown inside the films. Such silver NPs-titania films are known for their multicolor photochromic properties due to a photo-oxidation reaction of silver in the presence of titania under light excitation which is attributed to a plasmon induced charge separation. Here, the photoelectrochemical properties of these composite films have been investigated at different light wavelengths and chemical environment in order to characterize the light-induced redox reactivity modifications.

Development of Biphasic Formulations for Use in Electrowetting-Based Liquid Lenses with a High Refractive Index Difference.

Commercial electrowetting-based liquid lenses are optical devices containing two immiscible liquids as an optical medium. The first phase is a droplet of a high refractive index oil phase placed in a ring-shaped chassis. The second phase is electrically conductive and has a similar density over a wide temperature range.

Synthesis of Continuous Conductive PEDOT:PSS Nanofibers by Electrospinning: A Conformal Coating for Optoelectronics.

A process to synthesize continuous conducting nanofibers were developed using PEDOT:PSS as a conducting polymer and an electrospinning method. Experimental parameters were carefully explored to achieve reproducible conductive nanofibers synthesis in large quantities. In particular, relative humidity during the electrospinning process was proven to be of critical importance, as well as doping post-treatment involving glycols and alcohols.

Two liquids wetting and low hysteresis electrowetting on dielectric applications.

This study focuses on electrowetting using two immmiscible liquids on a dielectric coating. It is demonstrated that low contact angle of oil on the hydrophobic surfaces is a key parameter to obtain a low hysteresis system, below 2 degrees . On the basis of these results, three aspects of the wetting properties have been studied: the influence of the surface hydrophobic properties, the design of the liquids according to the hydrophobic surface, and a graphical method to solve the Bartell-Osterhof equation and predict the wetting properties of two liquids on a surface.