The Waterloo Institute for Nanotechnology (WIN) presents a seminar by Dr Carole Rossi, Research Director of the Laboratoire d'Analyse et d'Architecture des Systèmes (LAAS-CNRS), Université de Toulouse, France.
Nanoenergetics: A New Technological Area through the Integration of Reactive NanoMaterials into MEMS
Abstract
Over the past two decades, the rapid development of nanochemistry and nanotechnology has allowed the synthesis of various metal and oxides in the form of nanopowders, nanolayers, nanowires making it possible to produce new energetic nanostructures and nanomaterials. Thermite mixtures, intermetallic reactants often termed as reactive nanomaterials or reactive nanostructures, are widely studied for pyrotechnic applications at large, as a component of traditional gas generating material or more recently as new energetic compounds. The main line driving most of the works in reactive nanomaterials is to control the surface area and to maximize the intimacy between reactive reactants to increase the reaction rate, decrease the ignition delay, tune the energy burst delivery while improving safety. Recently, researchers have demonstrated that playing with the composition, stoichiometry as well as the nanostructures allows reaching not only high energy density, reduced impact sensitivity but also offers the possibility of producing a wide range of gas upon reaction. These new categories of energetic materials should lead to major breakthroughs in small size integrated pyrotechnical devices (called pyroMEMS) for applications in micro ignition, micro power source, micro actuation/propulsion, biological agents neutralization, electrical protections, and bonding.
My talk will be organized as follows. PyroMEMS field will be first overviewed. Then, I will discuss some of the main technological challenges and scientific issues related to the development of thermite based reactive nanomaterials and nanostructures with a focus on Al/CuO multilayered films. A fundamental understanding of the relationship between material structure, interfaces and performances such as energy release rate and reaction propagation rate will be presented. For PyroMEMS application, beside the energetic nanomaterial itself, another technological challenge associated with harvesting heat of the highly energetic reaction for practical applications entails the ignition of the reactive films within the MEMS devices. Given the high reactivity of material as well as high reaction temperature, only a small region of the material has to be heated to its ignition temperature to trigger the self-sustained combustion reaction. I will present manufacturing processes of reactive polymeric electro-thermal nanoheaters integrating Al/CuO multilayered films. The seminar will be concluded by overviewing some applications through the presentation of a few pyroMEMS devices integrating energetic nanomaterials.