The main objective of the laboratory of sonochemistry in complex fluids (LSFC) consists in fundamental studies of the mechanisms of sonochemical reactions in homogeneous solutions and heterogeneous systems. Studied systems are bound to research performed for the next generation of nuclear reactors, which aim at a sustainable development. Sonochemistry, i.e. the chemical effects of ultrasound, originates in acoustic cavitation: nucleation, growth and implosion of gas bubbles in liquids submitted to an ultrasonic field. The implosion occurs on the microsecond time scale and the collapse induces extreme local conditions of several thousand degrees and several hundred of bar pressure, with high cooling rates (~1010 K s-1). Recent studies demonstrated the formation of non-equilibrium plasma inside the bubble at collapse. This local concentration of energy constitutes the origin of the light emission by the cavitation bubbles (sonoluminescence), of the chemical activity in the bulk and of the evolution of heterogeneous systems. Each cavitation bubble, having for example a resonance size of ~150 μm at 20 kHz, can be considered as a high-temperature microreactor allowing physico-chemical reactions to occur. It does not need specific reactants to be added and does not generate additional wastes, hence adhering to the "green chemistry" principles.
The main tasks of the LSFC are to study: