Multi-Layer Structure and Performance of Superamphiphobic Photocatalytic Coatings Based on Edta-Biobr for No Degradation

Abstract

NO is one of the main pollutants in air pollution, and the number of highway tunnels is constantly increasing. Its unique semi-enclosed structure hinders the escape of car exhaust, causing serious pollution. In this paper, EDTA was used as a morphology regulator to synthesize hollow microspheres (EDTA-BiOBr) formed by the self-assembly of BiOBr nanoparticles. Epoxy resin was utilized as the film-forming material, while EDTA-BiOBr provided photocatalytic activity, and perfluorodecyl triethoxysilane (PFDTES) served as the low surface energy component. A superamphiphobic self-cleaning coating with photocatalytic was fabricated using the layer-by-layer spray method. The microstructure, chemical composition, optical, and electrochemical properties of the coating were characterized using techniques such as photoluminescence spectroscopy (PL), X-ray photoelectron spectroscopy (XPS), and Fourier transform infrared absorption spectroscopy (FT-IR). Under visible light irradiation, the degradation rate of NO by the coating reached 61.2%, and almost no NO2 was produced, indicating that the coating had good photocatalytic activity and high selective conversion efficiency for NO. The water contact angle (WAC) and olive oil contact angle (OAC) of the coating are 164.2° and 151.5°, respectively. After soaking in acidic, alkaline, and salt solutions, the contact angle (CA) remains above 150°, indicating that the coating has good superamphiphobic and chemical stability. Finally, the mechanism of green NO degradation was proposed, providing a theoretical and practical foundation for the degradation of NO in tunnels.

Keywords: BiOBr, NO degradation, Self-cleaning, Superamphiphobic, Tunnel inner wall coating