Robust under-liquid dual super-lyophobicity cement material for anti-fouling and oily wastewater treatment

Abstract

Materials of under-liquids (water/oil) dual super-lyophobicity require special micro/nano morphology. However, such material surfaces are mechanically weak and readily worn, which restricts their practical applications. Herein, we report a robust self-similar under-liquid dual super-lyophobicity anti-fouling cement which demonstrates stable underwater super-oleophobicity (θo/w > 150°) and under oil super-hydrophobicity (θw/o > 150°) via a simply mixed cement and water, without other organic reagents and professional preparation technology. The obtained material not only owns good under-liquids mechanical robustness but also has very excellent anti-fouling property. This surface material still has the anti-oil-fouling property once its surface is mechanically damaged, due to its surface self-similar functionality. Importantly, the surface maintained their excellent super-lyophobic functionality due to the similar property after turbulent jets (5 m range), abrasive belt wear, blade cutting (transverse cutting), highly-viscous tape peeling (VHB, 3 M), and ASTM standard adhesion (scratch spacing and cutting spacing). Cement could separate from oil/water mixtures, the separation efficiency for oil was above 97.5% at 30 cycles. Our study provides an eco-friendly, green, simple, low-cost, and easily mass-produced strategy to the fabrication of super-lyophobic materials in oil/water systems dual functional materials, which will benefit applications in diverse fields.