Hierarchical multilayer EDTA-BiOBr superamphiphobic coatings for enhanced eco-friendly photocatalytic degradation of nitric oxide

In this study, a BiOBr nanomaterial with a hollow microsphere structure was successfully prepared through ethylenediaminetetraacetic acid (EDTA) assisted morphology control. Based on this photocatalytic material, epoxy resin was utilized as the film-forming material, and perfluorodecyl triethoxysilaneserved as the low surface energy component. A superamphiphobic self-cleaning coating with photocatalytic was fabricated using the layer-by-layer spray method. The microstructure, NO oxidation performance, liquid wettability, self-cleaning, and durability of the coating were tested. The surface of the coating presents rough micro-nanostructures, endowing the coating with superior superhydrophobicity, the degradation rate of NO by the coating reached 61.2 % and has a low NO 2 conversion rate. The water contact angle and olive oil contact angle of the coating are 164.2° and 151.5°, respectively. After soaking 10 % aqueous solutions of NaCl, HCl, and NaOH for 48 h, the water contact angle remains above 150°, suggesting that the coating exhibits remarkable superamphiphobicity and chemical stability. Ultimately, a sustainable and efficient long-term NO purification and degradation mechanism of the coating is proposed. The design method and application of this coating are expected to have a positive impact on the purification treatment of automobile exhaust inside tunnels.