title: Bench-top method for fabricating glass-sealed nanodisk electrodes, glass nanopore electrodes, and glass nanopore membranes of controlled size.
abstract: A simple benchtop method of fabricating glass-sealed nanometer-sized Au and Pt disk electrodes, glass nanopore electrodes, and glass nanopore membranes is reported. The synthesis of all three structures is initiated by sealing the tips of electrochemically sharpened Au and Pt microwires into glass membranes at the end of a soda lime or lead glass capillary. Pt and Au nanodisk electrodes are obtained by hand polishing using a high-input impedance metal oxide semiconductor field effect transistor (MOSFET)-based circuit to monitor the radius of the metal disk. Proper biasing of the MOSFET circuit, based on a numerical analysis of the polishing circuit impedance, allows for the reproducible fabrication of Pt disk electrodes of radii as small as 10 nm. Significantly smaller background currents in voltammetric measurements are obtained using lead glass capillaries, a consequence of the lower mobility of Pb(2+) (relative to Na(+)) in the glass matrix. Glass nanopore electrodes and glass nanopore membranes are fabricated, respectively, by removal of part or all of the metal sealed in the glass membranes. The nanostructures are characterized by atomic force microscopy, steady-state voltammetry, and ion conductivity measurements.
authors.affiliation: Department of Chemistry, University of Utah, 315 S, 1400 E, Salt Lake City, Utah 84112, USA.
authors.forename: Bo
authors.initials: B
authors.lastname: Zhang
authors.forename: Jeremy
authors.initials: J
authors.lastname: Galusha
authors.forename: Peter G
authors.initials: PG
authors.lastname: Shiozawa
authors.forename: Gangli
authors.initials: G
authors.lastname: Wang
authors.forename: Adam Johan
authors.initials: AJ
authors.lastname: Bergren
authors.forename: Ronald M
authors.initials: RM
authors.lastname: Jones
authors.forename: Ryan J
authors.initials: RJ
authors.lastname: White
authors.forename: Eric N
authors.initials: EN
authors.lastname: Ervin
authors.forename: Chris C
authors.initials: CC
authors.lastname: Cauley
authors.forename: Henry S
authors.initials: HS
authors.lastname: White
mesh_terms: D015374:Biosensing Techniques / Q000295:instrumentation / Q000379:methods*; D017610:Calcium Compounds / Q000737:chemistry; D004553:Electric Conductivity; D004563:Electrochemistry; D004566:Electrodes; D005898:Glass; D006046:Gold / Q000737:chemistry*; D007477:Ions; D007854:Lead / Q000737:chemistry; D008567:Membranes, Artificial; D018625:Microscopy, Atomic Force; D049329:Nanostructures / Q000737:chemistry*; D053770:Nanowires / Q000737:chemistry; D010087:Oxides / Q000737:chemistry; D010984:Platinum / Q000737:chemistry*; D016062:Porosity; D012680:Sensitivity and Specificity; D012972:Sodium Hydroxide / Q000737:chemistry; D014173:Transistors, Electronic
chemical_list: D017610:Calcium Compounds; D007477:Ions; D008567:Membranes, Artificial; D010087:Oxides; D007854:Lead; D010984:Platinum; C004569:soda lime; D012972:Sodium Hydroxide; D006046:Gold