Column about our research field (Korean version):
Electroconvective Instability
On ion-selective surfaces such as ion-exchange membrane in electrodialysis, electrodes in electrochemical cell and reactive surfaces of catalyst, applied electric field can be generated chaotic flow patterns. This unstable and random vortices effectively mix ion concentration nearby the ion-selective surface, leading to energy-efficient mass flux. Understanding of this instability can be utilized for electrodialysis, electrochemical cell or lab on a chip platforms.
Diffusiophoresis
Under a concentration gradient, a charged particles can be moved without any external stimuli except for the concentration gradient. This is called as diffusiophoresis. The diffusiophoresis can be utilized as external power-free transport mechanism. Therefore, this phoretic mechanism would provide effective means for oil recovery, biomolecule manipulations or self-propelled microswimmer.
Ion Concentration Polarization (ICP)
If there is an interface of micro- and nano-scale domain, counter-ion can pass through the interface but co-ion cannot. Such ion-selective transport leads the formation of ion depletion zone and ion enrichment zone around the micro/nano interface. This is called as an ion concentration polarization. ICP is key mechanism for electrochemical desalination so that fundamental investigations about ICP shoulde be required for energy-efficient desalination system. Furthermore, ICP can be utilized as particle preconcentration mechanism as shown in video.