CuCo-LDHs-Based Photothermal and Magnetic Multifunctional Sponge for Efficient Removal of Oils and Microplastics from Water

In this article, a kind of multifunctional composite with magnetic actuation and photothermal conversion functions for oils and MPs adsorption in water was successfully fabricated through dip-coating method. Through a series of steps of grafting PDA, CuCo-LDHs, Fe 3 O 4 , and PDMS on melamine foam (MF) structure, a multifunctional composite sponge was designed, and was labeled as PDMS/Fe 3 O 4 /CuCo-LDHs/PDA@MF (PFCA). The PFCA shows remarkable photothermal conversion performance, the maximum surface temperature can attain 141.1 ℃ under simulated sunlight with intensity of 2.0   kW/m 2 . Meanwhile, the PFCA exhibits remarkable oil–water separation performance, the oil removal efficiencies of various oils are all higher than 99%. Besides, the PFCA presents good adsorption performance for MPs, the maximum removal efficiencies of MPs removal based on PE, PP and PS are 98.3%, 98.1% and 98.7%, respectively. Finally, the adsorption behavior of PFCA for MPs were studied, the MPs adsorption mechanism of PFCA was explored and p–π, π–π interaction, electrostatic force, hydrogen bonding, superhydrophobic effect and their synergistic effect were analyzed.