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Electrochemical NO 2 gas sensors: Model and mechanism for the electroreduction of NO 2
Author(s) -
Chang SiChung,
Stetter Joseph R.
Publication year - 1990
Publication title -
electroanalysis
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.574
H-Index - 128
eISSN - 1521-4109
pISSN - 1040-0397
DOI - 10.1002/elan.1140020506
Subject(s) - amperometry , electrode , electrocatalyst , electrochemical gas sensor , analyte , electrochemistry , materials science , analytical chemistry (journal) , chemistry , chromatography
Two types of sensing devices have been studied in order to elucidate the mechanism of response of amperometric gas sensors. A high‐surface‐area electrode (HSAE) sensor produces fast electrode reactions, and the steady‐state sensor signals are controlled either by permeation or by the supply of analyte to the sensor. For low‐surface‐area electrode (LSAE) sensors, a kinetically controlled signal is observed. A mechanism that involves a “chemically” induced changes in the gold electrode surface oxide coverage is proposed, and the activation energy for NO 2 reduction at a gold electrocatalyst is calculated. A general model of sensor response is proposed that can describe the behavior of the steady‐state response for both HSAE and LSAE sensors.