One-step facile fabrication of hydrophobic SiO2 coated super-hydrophobic/super-oleophilic mesh via an improved Stöber method to efficient oil/water separation

Abstract

To achieve effective oil/water separation, one-step facile fabricated hydrophobic SiO2 coated super-hydrophobic/super-oleophilic mesh (FSSM) via an improved Stöber method. Apparent contact angle was characterized by a contact angle meter (CA). SEM, FTIR and XPS were used to characterize the surface morphology and chemical composition of FSSM, individually. The super-hydrophobicity of the membrane was conferred by the multistage rough structure and low surface energy substances produced by the hydrolysis and polycondensation reactions of TEOS, DTMS and TMODS. Meanwhile, the effect of the proportion for silane coupling agents DTMS and TMODS on the hydrophobicity from claiming stainless steel network surfaces was investigated. The results showed that when DTMS: TMODS = 1:9 (n: n), the maximum apparent contact angle of FSSM was 153.3°, while the apparent contact angle of oil was 0°. The C, O and Si elements on the surface of FSSM increased by approximately 21%, 9% and 20% respectively. The FSSM can efficiently separate different oil/water mixtures (about 96%). Furthermore, FSSM showed excellent anti-corrosion (pH from 0 to 14) and remarkable reusability (about 40 cycles) and durability (exposure test at atmosphere for 35 days). The advantages of easy manufacture, stability and low cost of FSSM make it expected to be widely used in the field of oil-water separation.