Superhydrophobic DTMS/rGO-nanocomposites modified polyurethane sponge for efficient oil–water separation

ABSTRACT Dodecyltrimethoxysilane (DTMS)-modified reduced graphene oxide (rGO) nanocomposites were incorporated into polyurethane (PU) sponges by a combination of dip-coating and thermal curing reduction reaction to obtain a novel superhydrophobic DTMS-rGO-PU sponge for effective oil/water separation. The reaction conditions, such as the dip-coating solution concentration, the thermal curing reduction temperature, and the reaction time were demonstrated to be key factors in forming hierarchical DTMS-rGO nanocomposites, which significantly affected the surface wettability of the PU sponge. The resulting DTMS-rGO-PU sponge with a static water contact angle (WCA) of 152.2° displayed superior superhydrophobicity, and achieved an oil–water separation efficiency of 99.89% for various oil/water mixtures. This superhydrophobic sponge also showed minimal deterioration in its high oil adsorption capacity after 100 recycled adsorption operations. Furthermore, the as-prepared DTMS-rGO-PU sponge was proven to be physically and chemically stable and durable in harsh environmental conditions, suggesting its potential for industrial applications in oil spillage management.