title: Highly efficient electroosmotic flow through functionalized carbon nanotube membranes.
abstract: Carbon nanotube membranes with inner diameter ranging from 1.5-7 nm were examined for enhanced electroosmotic flow. After functionalization via electrochemical diazonium grafting and carbodiimide coupling reaction, it was found that neutral caffeine molecules can be efficiently pumped via electroosmosis. An electroosmotic velocity as high as 0.16 cm s(-1) V(-1) has been observed. Power efficiencies were 25-110 fold improved compared to related nanoporous materials, which has important applications in chemical separations and compact medical devices. Nearly ideal electroosmotic flow was seen in the case where the mobile cation diameter nearly matched the inner diameter of the single-walled carbon nanotube resulting in a condition of using one ion is to pump one neutral molecule at equivalent concentrations.
authors: Department of Chemical and Materials Engineering, University of Kentucky, Kentucky 40506, USA.
authors: Ji
authors: J
authors: Wu
authors: Karen
authors: K
authors: Gerstandt
authors: Mainak
authors: M
authors: Majumder
authors: Xin
authors: X
authors: Zhan
authors: Bruce J
authors: BJ
authors: Hinds
mesh_terms: D000537:Aluminum Oxide / Q000737:chemistry; D002110:Caffeine / Q000737:chemistry / Q000302:isolation & purification; D002234:Carbodiimides / Q000737:chemistry; D002412:Cations / Q000737:chemistry; D003979:Diazonium Compounds / Q000737:chemistry; D017097:Electric Impedance; D053841:Electroosmosis / Q000379:methods*; D008567:Membranes, Artificial; D037742:Nanotubes, Carbon / Q000737:chemistry*; D009942:Organometallic Compounds / Q000737:chemistry; D010316:Particle Size
chemical_list: D002234:Carbodiimides; D002412:Cations; D003979:Diazonium Compounds; D008567:Membranes, Artificial; D037742:Nanotubes, Carbon; D009942:Organometallic Compounds; C415768:tris(2,2'-bipyridyl)ruthenium(II); D002110:Caffeine; D000537:Aluminum Oxide