title: Tunable ionic transport for a triangular nanochannel in a polymeric nanofluidic system.
abstract: Recently, tremendous engineering applications utilizing new physics of nanoscale electrokinetics have been reported and their basic fundamentals are actively researched. In this work, we first report a simple and economic but reliable nanochannel fabrication technique, leading to a heterogeneously charged triangular nanochannel. The nanochannel utilized the elasticity of PDMS when it bonded with a micrometer-scale structure on a substrate. Second, we successfully demonstrated novel ionic transportations by tweaking the micrometer structures: (1) the transition of nonlinear ionic conductance depending on the nanochannel properties and (2) the ionic field-effect transistor. Nanochannel conductance has two distinguishable nonlinear regimes called the "surface-charge-governed" and the "geometry-governed" regime and its only individual overlooks were frequently reported. However, the transition between two regimes by adjusting nanochannel properties has not been reported due to the difficulty of functional nanochannel fabrication. In addition, a gate voltage was comfortably applied to the triangular nanochannel so that the field-effect ion transportation was reliably achieved. Therefore, presenting triangular nanochannels have critical advantages over its heterogeneous and tunable surface properties and thus, could be an effective means as an active fundamental to control and manipulate the ion-electromigration through a nanofluidic system.
authors.affiliation: Department of Mechanical Engineering, Pohang University of Science and Technology, San 31, Pohang, Gyeongbuk, Korea.
authors.forename: Bumjoo
authors.initials: B
authors.lastname: Kim
authors.forename: Joonseong
authors.initials: J
authors.lastname: Heo
authors.forename: Hyukjin J
authors.initials: HJ
authors.lastname: Kwon
authors.forename: Seong J
authors.initials: SJ
authors.lastname: Cho
authors.forename: Jongyoon
authors.initials: J
authors.lastname: Han
authors.forename: Sung Jae
authors.initials: SJ
authors.lastname: Kim
authors.forename: Geunbae
authors.initials: G
authors.lastname: Lim
mesh_terms: D004058:Diffusion; D004129:Dimethylpolysiloxanes / Q000737:chemistry*; D007477:Ions / Q000737:chemistry*; D008422:Materials Testing; D046210:Microfluidic Analytical Techniques / Q000379:methods*; D049329:Nanostructures / Q000737:chemistry* / Q000648:ultrastructure*; D009757:Nylons / Q000737:chemistry*; D010316:Particle Size; D016062:Porosity
chemical_list: D004129:Dimethylpolysiloxanes; D007477:Ions; D009757:Nylons; C085707:poly(dimethylsiloxane)-polyamide copolymer