Biography:

Christophe A Serra graduated in 1992 from the School of Chemical Engineering (ENSIC) in Nancy (France). He received his PhD in 1996 from the University Paul Sabatier in Toulouse (France). Then, he spent 18 months as a Postdoctoral Researcher at Rice University (Houston, TX). Since 1998, he has been a faculty member of the University of Strasbourg (France) teaching Chemical Engineering at the European Engineering School of Chemistry, Polymers and Materials Science (ECPM). His researches concern the development of new microfluidic-assisted polymer processes for the synthesis of architecture-controlled polymers and functional micro- and nanostructured polymer particles. In 2010, he was appointed as Full Professor at the University of Strasbourg and he joined in 2014 at the Charles Sadron Institute (ICS) becoming one of its Deputy Directors.

Abstract:

This lecture will address the development and application of advanced technologies in mixing and emulsification for the preparation of morphologically-complex nanocarriers for potential uses in pharmaceutics. Firstly, a micromixer-assisted nanoprecipitation process was used to get and to easily tune the size of Ketoprofen-loaded PMMA nanoparticles (100-200 nm). Combined with a commercial spray dryer, dry-state drug-loaded polymeric nanoparticles (NPs), which main physicochemical properties were close to those of non-spray-dried NPs, were successfully produced. This nanoprecipitation microprocess also allowed encapsulating 6 nm iron oxide NPs into 200 nm PMMA nanoparticles with a weight ratio of 60%. To increase the solid content of the above nanosuspension and get spherical polymeric NPs of smaller sizes (100 nm), an elongational-flow nanoemulsification method was used. Secondly, double nanoemulsions/nanohydrogels encapsulating a hydrophilic model drug in the aqueous core droplets/hydrogel were obtained by the combination of a commercial microfluidizer for the primary emulsion and a low energy emulsification method (spontaneous emulsification) for the double emulsification. The size of the double nanocarriers was varied by means of the surfactant to oil ratio (SOR) in the range 80 to 180 nm. Colocation of two fluorescent probes located in the core and in the shell was confirmed by fluorescence confocal microscopy. The spontaneous emulsification method was also employed to produce nanolipogels whose size could be tuned down to 60 nm. These nanolipogels were also loaded with iron oxide nanoparticles (6 nm) or gold nanoparticles (6 nm).

Biography:

Yasuhiro Sugawara acquired PhD in Experimental Physics at Tohoku University (Japan). He is a Professor for Applied Physics at Osaka University since 2002. He is one of the leading scientists in experimental Scanning Probe Microscopy (SPM). He is responsible for experimental research on nanophotonics, atom manipulation, characterization of nanostructure, and catalytic reaction on nanostructures. He was the Project Leader Of Grant-in-Aid for Scientific Research (S) and Core Research for Evolutionary of Science and Technology (CREST), which were the biggest research projects in Japan.

Abstract:

Among the surface characterization techniques at the atomic scale, atomic force microscopy (AFM) has become a powerful tool for investigating the surface properties and has been extended to manipulate atoms, enabling the creation of novel nanostructures, particularly on insulator surfaces. On the basis of AFM, Kelvin probe force microscopy (KPFM) and electrostatic force microscopy (EFM) have been widely used to measure surface potential distributions, charge transfer and electronic/electrical properties, etc. KPFM has been applied to various surfaces with atomic resolution, including conductive, semiconductor and insulating surfaces, such as in imaging the charge distribution within a molecule. The underlying principle of KPFM is as follows: the contact potential difference (CPD) between the tip and the sample surface is detected from the shift in resonance frequency or the amplitude of the cantilever by applying AC bias voltage, which modulates the electrostatic interaction force between the tip and the sample. A DC bias voltage is used to nullify oscillating electrical forces from the CPD. In atomic-resolution KPFM, the CPD is specifically referred to as the local contact potential difference (LCPD). The surface potential distribution measured using KPFM is influenced by the CPD between a tip and surface, the effect of stray capacitance of a cantilever, fixed monopole charges, and dipole moment on surfaces and interfaces. The interpretation of atomic scale KPFM contrast studies has been controversial. Here, we describe the investigation about the contrast mechanism in KPFM with atomic resolution. First, we investigate the effect of stray capacitance on surface potential measurement using KPFM. Next, we describe the investigation of the surface potential distribution on a TiO₂ (110) 1×1 surface by KPFM and atom-dependent bias-distance spectroscopic mapping. Then, we describe a new multi-image method for obtaining the frequency shift, tunneling current and LCPD on a TiO₂ (110) 1×1 surface with atomic resolution.

Biography:

Katerina Soulantica received her PhD in Chemistry from the University of Athens (Greece). After a Post-Doctoral Fellowship in the University of Valladolid (Spain) she joined the group of B Chaudret in the Laboratoire de Chimie de Coordination (Toulouse) and worked on the synthesis of metallic nanoparticles. She then joined the Laboratoire de Physique et Chimie des Nano-Objets (Toulouse). She is interested in the synthesis and formation mechanism of nanocrystals, in the tailoring of their physical and chemical properties through their structure, as well as in the design of multifunctional nanosystems for applications spanning from magnetic recording and biosensing to catalysis. 

Abstract:

The recent progress in the synthesis of colloidal nanocrystals by chemical routes has made available a great number of nanomaterials in a variety of sizes and shapes. Implementation of nanoscale objects in technologically important domains depends on the possibility to integrate them in various systems. Even for the best adapted candidate, some inherent characteristics are very often incompatible with specific requirements associated to each application. Magnetic nanocrystals constitute a class of materials that can be used in several applications such as magnetic recording, permanent magnets, catalysis, and biomedicine. Taking as an example metallic cobalt nanocrystals, we will discuss how chemistry can appropriately modify their shape, composition and organization, (Figure) towards applications in magnetic recording, biomolecular in vitro detection and catalysis. 

Biography:

Prof Zhu’s research interests exist in advanced catalysis, gas/liquid adsorption and separation, direct carbon fuel cells and solid oxide fuel cells. His publications include one edited book, 8 book chapters, and over 220 journal papers. He holds 6 patents, 3 patents have been licensed to the industrial sponsor. He has raised a total research funding from government and industries in excess of $20 million. He is the recipient of a number of awards, including RK Murphy Medal 2013, Freehills Award IChemE 2011, 2nd place Innovator of the Year Award Global IChemE 2011, the University of Queensland (UQ) Foundation Research Excellence Award in 2007. 

Abstract:

Solid oxide fuel cells (SOFCs) can effectively convert the chemical energy of fuels into electricity at an efficiency up to 60%. They typically operate at high temperature (800-1000^oC) resulting in high costs, materials compatibility and durability challenges. Developing SOFCs that can work at intermediate temperature (500-750 ^oC) has thus been attracting considerable attentions. The performance of the cathode is the largest hurdle to the full realization of low temperature SOFCs. In this talk, we will introduce our recent studies on 3D Heterostructured Catalysts for highly efficient oxygen reduction reaction in SOFCs.