title: Capillarity ion concentration polarization as spontaneous desalting mechanism.
abstract: To overcome a world-wide water shortage problem, numerous desalination methods have been developed with state-of-the-art power efficiency. Here we propose a spontaneous desalting mechanism referred to as the capillarity ion concentration polarization. An ion-depletion zone is spontaneously formed near a nanoporous material by the permselective ion transportation driven by the capillarity of the material, in contrast to electrokinetic ion concentration polarization which achieves the same ion-depletion zone by an external d.c. bias. This capillarity ion concentration polarization device is shown to be capable of desalting an ambient electrolyte more than 90% without any external electrical power sources. Theoretical analysis for both static and transient conditions are conducted to characterize this phenomenon. These results indicate that the capillarity ion concentration polarization system can offer unique and economical approaches for a power-free water purification system.
authors.affiliation: Department of Electrical and Computer Engineering, Seoul National University, Seoul 08826, South Korea.
authors.forename: Sungmin
authors.initials: S
authors.lastname: Park
authors.affiliation: Department of Mechanical and Aerospace Engineering, Seoul National University, Seoul 08826, South Korea.
authors.forename: Yeonsu
authors.initials: Y
authors.lastname: Jung
authors.affiliation: Department of Electrical and Computer Engineering, Seoul National University, Seoul 08826, South Korea.
authors.forename: Seok Young
authors.identifier: http://orcid.org/0000-0001-6747-337X
authors.initials: SY
authors.lastname: Son
authors.affiliation: Department of Electrical and Computer Engineering, Seoul National University, Seoul 08826, South Korea.
authors.forename: Inhee
authors.initials: I
authors.lastname: Cho
authors.affiliation: Department of Electrical and Computer Engineering, Seoul National University, Seoul 08826, South Korea.
authors.forename: Youngrok
authors.initials: Y
authors.lastname: Cho
authors.affiliation: Department of Electrical and Computer Engineering, Seoul National University, Seoul 08826, South Korea.|Institute of Advanced Machines and Design, Seoul National University, Seoul 08826, South Korea.
authors.forename: Hyomin
authors.initials: H
authors.lastname: Lee
authors.affiliation: Department of Mechanical and Aerospace Engineering, Seoul National University, Seoul 08826, South Korea.|Institute of Advanced Machines and Design, Seoul National University, Seoul 08826, South Korea.|Big Data Institute, Seoul National University, Seoul 08826, South Korea.
authors.forename: Ho-Young
authors.initials: HY
authors.lastname: Kim
authors.affiliation: Department of Electrical and Computer Engineering, Seoul National University, Seoul 08826, South Korea.|Big Data Institute, Seoul National University, Seoul 08826, South Korea.|Inter-university Semiconductor Research Center, Seoul National University, Seoul 08826, South Korea.
authors.forename: Sung Jae
authors.initials: SJ
authors.lastname: Kim