Development of Electrolyte-Free Ozone Sensors using Boron-Doped Diamond Electrodes.

Analytical Chemistry (Impact Factor: 5.7). 04/2013; DOI: 10.1021/ac400043b
Source: PubMed

ABSTRACT The electrochemical detection of dissolved ozone in water was examined using boron-doped diamond (BDD) electrodes. A well-defined reduction peak was observed at ~380 mV for H-terminated BDD, whereas it was observed at ~200 mV in the case of O-terminated BDD for ozone solution in a 0.1 M phosphate buffer solution at pH 7. The peak potential for ozone reduction was selective with respect to oxygen reduction at both H- and O-terminated BDD electrodes, whereas it occurred at approximately the same potential as oxygen reduction at other types of solid electrodes, including glassy-carbon, platinum, and gold electrodes. Interference from chlorine was not observed in lower concentration than 0.03 mM ClO-. Furthermore, in order to apply the detection technique to electrolyte-free media, BDD microelectrodes were also used. A linear calibration curve for dissolved ozone in water could be achieved between concentrations of 0.49 to 740 μM, with an estimated detection limit (S/N = 3) of 0.185 μM (S/N=3). Excellent stability was demonstrated for repetitions of these calibration curves performed in 3 consecutive days.

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