Simple and sensitive determination of hydroxyl radical in atmosphere based on an electrochemically activated glassy carbon electrode

ABSTRACT

The hydroxyl radical (•OH) plays important roles in environment and health problems. However, the short life time and low concentrations of •OH limited its detection. In this work, a simple method has been successfully performed for the sensitive detection of hydroxyl radical based on an activated glassy carbon electrode (AGCE).4-hydroxybenzoic acid (4-HBA) was used as a trapping agent for •OH radicals, leading to the production of electroactive 3,4-dihydroxybenzoic acid (3,4-DHBA). Different procedures including polarisation and cyclic voltammetry in acid or base solutions have been used to activate the glassy carbon electrodes. The electrochemical behaviours of 3,4-DHBA on these activated electrodes were studied and compared. Experimental results showed that the glassy carbon electrode polarised in H₂SO₄ (AGCE-P/H₂SO₄) has the greatest sensitivity and reproducibility to 3,4-DHBA. 3,4-DHBA performed a linear relationship from 1.0 × 10⁻⁷ to 1.0 × 10⁻⁴ M on the AGCE-P/H₂SO₄. The detection limit was down to 6.2 × 10⁻⁸ M. This method has been successfully applied for the detection of hydroxyl radical levels in atmosphere without separation and purification process.

KEYWORDS:

• Hydroxyl radical
• detection
• activated electrode
• atmosphere

Acknowledgements

The authors gratefully acknowledge NSFC (21575124, 21675140, 21275124 and 21275125), PAPD and TAPP of Jiangsu Higher Education Institutions, the High-end Talent Project of Yangzhou University, the 14th Six talent peaks project in Jiangsu Province (SWYY-085), Higher Education Outstanding Scientific and Technological Innovation Team of Jiangsu Province (2017-6).

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

The authors gratefully acknowledge NSFC [21575124, 21675140, 21275124 and 21275125], the High-end Talent Project of Yangzhou University and the 14th Six talent peaks project in Jiangsu Province [SWYY-085].