Anion-exchange membrane-separated electrochemical cells enable the use of sacrificial anodes for hydrogen peroxide detection with enhanced dynamic ranges

Abstract

Conventionally, both a working and counter electrode are housed in a single cell to form an electrochemical device for quantification of various analytes. For reductive sensing of hydrogen peroxide, however, analyte losses due to oxidation and catalytic decomposition on the counter electrode are significant, rendering such devices unsuitable for continuous monitoring of analyte concentration changes over time. Further, only chemically inert materials such as platinum can be used to construct the counter electrode, where their high cost limits potential applications. To circumvent such issues, an anion-exchange membrane was employed to fabricate a two-chamber device housing each electrode in each individual chamber, to physically prevent the counter electrode from interfering with working electrode analysis. Such a design enables the use of sacrificial anodes as the counter electrodes, thereby significantly expanding the linear range of detection, improving sensitivity, and reducing device cost.