Hybrid interface effect of g-C3N4/ZnO nanocomposites on the photoelectrochemical cathodic protection of 304 stainless steel in chloride solution

Authors

• Htet Yadanar Soe
• Thanate Na Wichean
• Jularpar Sunttiprapar
• Parichart Chaum
• Gasidit Panomsuwan
• Oratai Jongprateep
• Ratchatee Techapiesancharoenkij

Publication Date

2026

Abstract

The development of efficient and environmentally friendly corrosion protection systems for metals in aggressive environments has become a critical area of research, particularly for stainless steel used in marine and industrial applications. In this study, a series of graphitic carbon nitride (g-C3N4) and zinc oxide (ZnO) composites with varying g-C3N4 weight ratios (10 wt% and 30 wt%), are integrated to form heterojunction structures with enhanced charge separation and interfacial activity. The g-C3N4/ ZnO (ZCN) composite thin films were prepared using a facile thermal mixing method and were characterized using XRD, SEM, BET, FTIR, UV-Vis, and PL to confirm their structural, morphological, and optical properties. Electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization measurements of the ZCN thin films and 304 stainless steel samples under 3.5 wt% NaCl solution showed higher photocurrent density, more negative photopotential displacement, and lower charge-transfer resistance, confirming accelerated electron migration from the ZCN thin film to the stainless-steel substrate. The open circuit potential (OCP) of the steel shifted negatively under illumination, confirming the generation of photogenerated cathodic protection. These results highlight the critical role of the hybrid interface and optimized g-C3N4 content in improving light-driven corrosion protection systems. The 10 wt% g-C3N4/ZnO nanocomposite offers a promising approach for the development of efficient photo-electrochemical coatings aimed at protecting stainless steel in harsh electrolyte environments.

DOI

10.55713/jmmm.v36i3.2642

First Page

1

Last Page

11

Recommended Citation

Yadanar Soe, Htet; Na Wichean, Thanate; Sunttiprapar, Jularpar; Chaum, Parichart; Panomsuwan, Gasidit; Jongprateep, Oratai; and Techapiesancharoenkij, Ratchatee (2026) "Hybrid interface effect of g-C3N4/ZnO nanocomposites on the photoelectrochemical cathodic protection of 304 stainless steel in chloride solution," Journal of Metals, Materials and Minerals: Vol. 36: No. 3, Article 14.
DOI: 10.55713/jmmm.v36i3.2642
Available at: https://digital.car.chula.ac.th/jmmm/vol36/iss3/14