Agave-Angustifolia-like Cu3Mo2O9 Nanoplate-Coated Copper Mesh for Effective Emulsion Separation and Photocatalytic Degradation of Soluble Dyes

Significant progress has been made in the development of membranes characterized by high permeation flux, special wettability, selectivity, and stability during oily wastewater separation. However, more research is needed in multitasking membranes. Herein, we introduce a facile strategy of fabricating a superhydrophilic and underwater superoleophobic agave-angustifolia-like Cu3Mo2O9 nanoplate-coated copper mesh membrane via subsequent chemical oxidation, hydrothermal deposition, and calcination methods. The synergistic effect of the hierarchical structure and photocatalytic activity of the Cu3Mo2O9 coating endowed the as-fabricated membrane with superwettability and self-cleaning ability, resulting in high permeation flux (up to 3503.18 L·m–2·h–1 for surfactant-free emulsions and 917.20 L·m–2·h–1 for surfactant-stabilized emulsions) and low oil residues in the filtrate (COD value of 11.4 mg L–1 for surfactant-free emulsions and 86.8 mg L–1 for surfactant-stabilized emulsions) during oil-in-water emulsion separation, as well as photocatalytic dye degradation capabilities for methylene blue (92.4%) and rhodamine B (68.6%). Furthermore, the as-fabricated membrane exhibited favorable chemical stability and abrasive resistance. The strategy presented in this work provided a method to produce a durable membrane for efficient oil–water separation with photocatalytic properties and can withstand harsh environments.