Modulation of titanium dioxide/graphene interface by Mg2+ doping: Titanium dioxide coatings with conductive, corrosion-resistant and superhydrophobic features

Abstract

Conductive coatings show great application potential in the fields of electronic devices, energy storage and conversion, and primers for new energy vehicles, but their performance bottlenecks such as corrosion resistance, hydrophobicity, and dispersibility limit their wide applications. In order to solve these problems, this paper innovatively proposes a conductive coating (Mg-TG) composite of titanium dioxide and graphene via Mg²⁺ modification in the acetic acid system. By precisely modulating the doping amount of Mg²⁺, the electronic structure and physical properties of titanium dioxide are significantly optimised, and an efficient conductive network is formed with graphene, successfully constructing a high-performance composite powder with a low resistivity as low as 0.083 Ω cm. Advanced characterisation techniques (XPS) and density-functional-theoretic calculations (DFT) indicate that the formation of defective engineering activates lattice oxygens, leading to electronic structure modulation and material valence bonding changes, thus constructing efficient electron transport channels (Ti-O-C, Mg-O-C) and ensuring uniform distribution and fast electron circulation in the coating. In addition, through the Tafel curve test, water contact angle test (WCA) and coating experiments, it was demonstrated that the Mg²⁺ modification effectively improved the corrosion resistance, hydrophobicity and dispersibility of the material. In this way, the coating not only effectively resists the ability of corrosive media and extends its service life, but also maintains stable electrical properties in humid environments and avoids performance degradation due to moisture penetration. At the same time, the modification of Mg²⁺ also promotes the uniform dispersion of the material and improves the activity and stability of the coating, laying a solid foundation for efficient performance in a variety of application scenarios.