title: Electrochemistry through glass.
abstract: In this Article we have used new approaches to investigate a well-known chemical process, the propagation of electrochemical signals through a thin glass membrane. This process, which has been extensively studied over the last century, is the basis of the response of a potentiometric glass pH sensor; however, no amperometric glass sensors have yet been reported because of its high ohmic resistance. Voltammetry at nanoelectrodes has revealed that water molecules can diffuse through nanometre-thick layers of dry glass and undergo oxidation/reduction at the buried platinum surface. After soaking for a few hours in an aqueous solution, voltammetric waves of other redox couples, such as Ru(NH(3))(6)(3+/2+), could also be obtained at the glass-covered platinum nanoelectrodes. This behaviour suggests that the nanometre-thick insulating glass sheath surrounding the platinum core can be largely converted to hydrated gel, and electrochemical processes occur at the platinum/hydrogel interface. Potential applications range from use in nanometre-sized solid-state pH probes and determination of the water content in organic solvents to glass-modified voltammetric sensors and electrocatalysts.
authors.affiliation: Department of Chemistry and Biochemistry, Queens College-CUNY, Flushing, New York 11367, USA.
authors.forename: Jeyavel
authors.initials: J
authors.lastname: Velmurugan
authors.forename: Dongping
authors.initials: D
authors.lastname: Zhan
authors.forename: Michael V
authors.initials: MV
authors.lastname: Mirkin
mesh_terms: D002384:Catalysis; D003300:Copper / Q000737:chemistry*; D004563:Electrochemistry; D004566:Electrodes; D005898:Glass / Q000737:chemistry*; D020100:Hydrogels; D053768:Metal Nanoparticles / Q000737:chemistry*; D036103:Nanotechnology; D010084:Oxidation-Reduction; D010984:Platinum / Q000737:chemistry*; D013499:Surface Properties
chemical_list: D020100:Hydrogels; D010984:Platinum; D003300:Copper