Robust and Durable Superhydrophobic Polythiophene/SiO₂ Coated Cotton Fabric for Versatile Oil–Water Separation

Abstract

With the development of industrialization, environmental pollution problems (e.g., oily water discharge and oil spill accidents) are becoming increasingly severe. The efficient and economic treatments for oily sewage are urgently needed and remain a huge challenge. Here, a robust and durable superhydrophobic material with the contact angle above 160° is prepared by coating SiO2 particles/polythiophene on cotton fabrics through a sol–gel process and an oxidation coupling polymerization. The polythiophene/SiO2 coated cotton fabric displays excellent resistance to ultraviolet irradiation, high and low temperatures, acid and salt solution immersion, organic solvent immersion, and good mechanical abrasion durability, antidirt and antifrost properties. The modified fabric is successfully applied as a filter to separate oil–water mixtures by gravity with high separation efficiency and excellent reusability. Moreover, superhydrophobic absorbers can be easily prepared from common 3D porous materials such as a sponge wrapped with the modified fabric for the effective collection of oil. Both immiscible oil–water mixtures and emulsions (oil‐in‐water and water‐in‐oil) can be separated even under harsh conditions (acidic solution or artificial seawater). This work provides a facile and selectable solution to treat oily sewage and leads to new ways of efficient oil–water separation.

Superwetting surfaces for filtration separation of high-viscosity raw petroleum/water mixtures

“…3g). 56 First, the cotton fabric was coated with micro-nano SiO 2 via a gel–sol method, and then polythiophene (PTh) was conjugated and modified by oxidative coupling polymerization. Experiments have shown that the modified fabric has good superhydrophobicity with a contact angle of up to 160° in water.…”

Robust graphene/poly(vinyl alcohol) aerogel for high‐flux and high‐purity separation of water‐in‐oil emulsion and its computational fluid dynamic simulation

“…Aphra et al 22 reported simple synthesis of Janus mixed sustainable cellulose nanofibers (CNFs) sponge with asymmetric wettability, superb mechanical properties, and excellent separation purity for oil–water emulsions. Bai et al 23 coated SiO 2 particles/polythiophene on the cotton fabric through sol–gel process and oxidative coupling polymerization and prepared a strong and durable superhydrophobic material with contact angle greater than 160. This material was employed for gravity separation of oil–water mixture with high separation purity and reusability.…”