Day 1 :
ICMCB, University of Bordeaux, France
Keynote: Nano structuration of thin films an alternative solution for hard chromium coating replacement
Time : 09:30-10:05
Angeline Poulon-Quintin is an Associate Professor at the University of Bordeaux and ICMCB. She has a long experience in the correlation between process parameters, textures, microstructures and properties of structural and functional materials. Her current interests range from the search for innovative multifunctional coatings to the development of green processes to elaborate intermetallic compounds and/or nanostructured materials with innovative architecture, for applications in energy, aerospace and aeronautical industries. She is a Specialist in fine characterization with an extended recognized experience in electronic microscopy and physico-chemical techniques. She has co-authored 36 peer-reviewed articles, 40 oral presentations, 14 invited conferences and 4 patents.
Hard chrome plating is used by Original Equipment Manufacturer to provide sealing surface for hydraulic seals, wear resistance to moving parts and corrosion protection to a wide variety of components for aircraft. The main areas of hexachromium using processes are mechanical, automotive, aerospace and military. By improving tribological properties (superior hardness) and corrosion resistance (natural ability to react with element such as oxygen), hard chromium can lower energy consumption of moving parts and machinery, reduce the need to replace parts frequently, leading to reduce waste and improve efficiency. The hard chrome plating is a powerful, simple and cheap process. From an environmental point of view, this process itself involves the use of highly toxic substances, such Cr6+ and lead compounds The Restriction of Hazardous substances Directive (Reach) was issue, banning several toxic substances including Cr6+. Hard chromium electroplating has been also classified by the U.S. Environmental Protection Agency (EPA) as an environmentally unfriendly process. Now, several hard chrome plating alternatives have been developed depending on the application:1) High Velocity Oxy-Fuel thermal sprays for repairs and for the deposition of high-quality hard-metals and metals coatings, 2) Electro and electroless plates; 3) Vacuum coating, 4) Heat treatments, 5) Laser and weld coatings. Due to its complex mix of properties, no single coating will replace hexavalent chromium in all applications. In this presentation, the exploration of the potential of nanostructured coating elaborated with innovative processes, will be discuss as an efficient alternative solution for hard chromium coating replacement. The opportunity to use architecture coating will be presented. Various families of materials will illustrate the correlation between process-Nano structuration and final properties.
National Tsing Hua University, Taiwan
Time : 11:35-12:10
Tsan-Yao Chen is an Associate Professor in the Department of Engineering and System Science at National Tsing Hua University. With more than 10 years of experience in Materials Characterization and 6 years’ experience in electronic device (MEMS and IC) failure analysis of multiple executives by Synchrotron Light Source Techniques (at NSRRC, Taiwan). He conducts fundamental materials development in green energy applications including solar cell, fuel cell, and CO2 conversion, water sensing with worldwide collaboration at National rank research team in Russia, USA, Italy, Japan (SPring-8), and UK. He is also hosting research projects from academic and industrial funds on physical chemistry researches and environment sensing technologies.
Surface decoration is an effective assessment for improving chemical stability of nanocatalysts. In this study, we demonstrate that the dimension of the surface decoration can be manipulated down to atomic scale. Apart from using noble metals, atomic scaled Pt clusters were employed to improve the oxygen reduction reaction performance of catalysts. Those clusters are decorated in surface defect regions of Cocore-Pdshell (Co-Pd) nanoparticles by using self-aligned nanocrystal growth followed by atomic quench with strong reduction agent. They localize electrons from neighboring atoms and boost activity of Co-Pd NP in ORR. With a proper reaction time and loading control, the Pt cluster decorated Co - Pd nanoparticles enhance its mass activity by 340 times as compared to that of commercial Pt catalysts in an alkaline electrolyte of 1.0M KOH.
Schematic representation for the atomic decoration in core-shell nanoparticle and the corresponding oxygen reduction reaction pathways.