TY  - JOUR
AU  - Hüske, Martin
AU  - Stockmann, Regina
AU  - Offenhäusser, Andreas
AU  - Wolfrum, Bernhard
TI  - Redox cycling in nanoporous electrochemical devices
JO  - Nanoscale
VL  - 6
IS  - 1
SN  - 2040-3372
CY  - Cambridge
PB  - RSC Publ.
M1  - FZJ-2014-00285
SP  - 589 -598
PY  - 2014
AB  - Nanoscale redox cycling is a powerful technique for detecting electrochemically active molecules, based on fast repetitive oxidation and reduction reactions. An ideal implementation of redox cycling sensors can be realized by nanoporous dual-electrode systems in easily accessible and scalable geometries. Here, we introduce a multi-electrode array device with highly efficient nanoporous redox cycling sensors. Each of the sensors holds up to 209[thin space (1/6-em)]000 well defined nanopores with minimal pore radii of less than 40 nm and an electrode separation of [similar]100 nm. We demonstrate the efficiency of the nanopore array by screening a large concentration range over three orders of magnitude with area-specific sensitivities of up to 81.0 mA (cm−2 mM−1) for the redox-active probe ferrocene dimethanol. Furthermore, due to the specific geometry of the material, reaction kinetics has a unique potential-dependent impact on the signal characteristics. As a result, redox cycling experiments in the nanoporous structure allow studies on heterogeneous electron transfer reactions revealing a surprisingly asymmetric transfer coefficient.
LB  - PUB:(DE-HGF)16
UR  - <Go to ISI:>//WOS:000328673000070
C6  - pmid:24247480
DO  - DOI:10.1039/c3nr03818a
UR  - https://juser.fz-juelich.de/record/150206
ER  -