Fabrication of a nanoporous dual-electrode system for electrochemical redox cycling

Martin Hüske, Bernhard Wolfrum

Research output: Contribution to journalArticlepeer-review

7 Scopus citations

Abstract

Nanoporous electrodes are promising tools for highly sensitive electrochemical detection of molecules by redox cycling. In here, we report on a novel approach for the on-chip fabrication of nanoporous dual-electrode systems. The fabrication is based on template assisted dry etching into an electrode-insulator-electrode structure using a nanoporous alumina film as a mask. The mask itself is patterned by directly anodizing an aluminum layer on top of the chip. Homogeneous growth of the alumina nanopores on a wafer scale is achieved by adding a titanium intermediate film between the top electrode and the aluminum substrate as a stopping layer. The resulting electrodes are separated by approximately 100nm and have pore diameters in the range of 30-50nm. Thus they are ideally suited for redox cycling experiments based on fast diffusion of molecules between the electrodes. Integrating this process into microfabricated electrode structures promises to yield a stable and sensitive electrochemical sensor platform. Redox cycling scheme for a nanoporous dual-electrode system. The close distance of anode and cathode provides a short diffusion path of oxidized and reduced molecules, as depicted by the arrows. The inlet shows a close-up of the molecules within a pore. Different colours indicate different oxidation states.

Original languageEnglish
Pages (from-to)1265-1269
Number of pages5
JournalPhysica Status Solidi (A) Applications and Materials Science
Volume208
Issue number6
DOIs
StatePublished - Jun 2011
Externally publishedYes

Keywords

  • anodized alumina
  • nanofabrication
  • nanoporous electrodes
  • redox cycling sensor

Fingerprint

Dive into the research topics of 'Fabrication of a nanoporous dual-electrode system for electrochemical redox cycling'. Together they form a unique fingerprint.

Cite this