Photoelectrochemical cathodic protection of amorphous zinc oxide coating on hot rolled steel SS400 in a 3 wt% NaCl solution and a Na2S-NaOH solution

Authors

• Phatchara Wipataphan
• Worapot Sripianem
• Naw Blessing Oo
• Thanate Na Wichean
• Boossayamas Dachbumroong
• Oratai Jongprateep
• Gasidit Panomsuwan
• Naray Pewnim
• Ratchatee Techapiesancharoenkij

Publication Date

2021

Abstract

The photoelectrochemical cathodic protection of amorphous ZnO thin-film coating on hot rolled steel SS400, in the 3 wt% NaCl environment, was investigated. The ZnO thin film was coated on a SS400 substrate at 200℃ using the spray pyrolysis technique. The x-ray diffractometry analysis confirmed the amorphous ZnO coatings. Two different types of the electrochemical cells were used: a single-cell and a double-cell system. Two different types of the photoelectrolytic solutions were compared: (i) 0.1 M Na2S + 0.2 M NaOH and (ii) 3 wt% NaCl solution. The ZnO-coated SS400 samples were subjected to potentiostatic polarization testing under dark and UV conditions, with the immersion of either Na2S-NaOH or NaCl solution. The photoelectrochemical analysis showed that the photocathodic protection on SS400 by the ZnO coating could be demonstrated with the photoelectrolytic solution of Na2S-NaOH. The voltage was negatively shifted and the current density was increased with the UV irradiation on the ZnO coating, immersing in the Na2S-present solution. The ZnO coating was also stable in the Na2S-NaOH solution. The microstructural analyses with Optical Microscope and Scanning Electron Microscope were conducted to support the photoelecrochemical analyses.

First Page

129

Last Page

142

Recommended Citation

Wipataphan, Phatchara; Sripianem, Worapot; Blessing Oo, Naw; Na Wichean, Thanate; Dachbumroong, Boossayamas; Jongprateep, Oratai; Panomsuwan, Gasidit; Pewnim, Naray; and Techapiesancharoenkij, Ratchatee (2021) "Photoelectrochemical cathodic protection of amorphous zinc oxide coating on hot rolled steel SS400 in a 3 wt% NaCl solution and a Na2S-NaOH solution," Journal of Metals, Materials and Minerals: Vol. 31: No. 4, Article 18.
Available at: https://digital.car.chula.ac.th/jmmm/vol31/iss4/18