Enhancement of the Activity and Stability of PbO2 Electrodes by Modifying with Polydimethylsiloxane. Issue 11 (1st January 2018)

• Record Type: Journal Article
• Authors: He, Zhiqiao; Zhou, Jiajie; Huang, Xinwen; Zhang, Shihan; Song, Shuang
• Is Part Of: Journal of the Electrochemical Society. Volume 165:Issue 11(2018)
• Page Start: H717
• Page End: H724
• Publication Date: 2018-01-01
• Subjects: Electrochemical degradation -- polydimethylsiloxane -- Ti/Sn-SbOx/PbO2 electrode; Electrochemistry -- Periodicals; 541.3705
• DOI: 10.1149/2.0791811jes
• Languages: English
• ISSNs: 0013-4651

Abstract

Abstract : The β-PbO2 of a Ti/Sn-SbOx /PbO2 electrode was modified with polydimethylsiloxane (PDMS) (Ti/Sn-SbOx /PbO2 -PDMS) through a facile electrodeposition method. The results from scanning electron microscopy, energy-dispersive spectrometry and X-ray diffraction demonstrated that the PDMS was irreversibly adsorbed on the β-PbO2 of Ti/Sn-SbOx /PbO2 -PDMS, leading to a decrease in the crystal size, surface cracks and preferential growth trend of β-PbO2 . Compared with its PDMS-unmodified counterparts, the Ti/Sn-SbOx /PbO2 -PDMS electrode exhibited relatively higher activity, selectivity and stability in the anodic oxidation of p -chlorophenol. Moreover, the Ti/Sn-SbOx /PbO2 -PDMS electrode was more stable than the Ti/Sn-SbOx /PbO2 electrode, as evidenced by the accelerated life test. Based on the quantitative measurements of contact angle, hydroxyl radicals (HO) and the initial surface concentration of various p -substituted phenols, including p -cresol, p -methoxyphenol, phenol, and p -chlorophenol, and with the help of electrochemical characterization of linear sweep voltammetry, it could be concluded that the improved electrochemical activity and stability of Ti/Sn-SbOx /PbO2 -PDMS originated from the enhanced hydrophobicity of the electrode surface. Different from a traditional Ti/Sn-SbOx /PbO2 electrode with adsorbed HO as the dominant active species, the Ti/Sn-SbOx /PbO2 -PDMS with a hydrophobic surface favors the generation of more free HO.