Facile fabrication of TiO2-functionalized material with tunable superwettability for continuous and controllable oil/water separation, emulsified oil purification, and hazardous organics photodegradation

The sustainable development of modern industry and the frequent emergence of marine oil spills have caused a significant and far-reaching impact on water resources, prompting individuals to develop an advanced technology or material for the solution of oily wastewater. Therefore, a functionalized material herein has been successfully fabricated by decorating cotton surface with photocatalytic titanium dioxide (TiO2) nanoparticles and chemical components containing pH-sensitive carboxyl groups through a simple, green and cost-effective approach. By combining the nano-roughness structure of the surface with the suitable surface components, endowing the as-obtained cotton with the splendid properties of adjustable surface wettability, photocatalytic degradation and durability. Based on the tunable wettability of the resulted cotton, it can intelligently separate two forms of oil/water mixtures involving stratified oil-water mixtures and surfactant-stabilized emulsions with prominent separation efficiency. Simultaneously, by virtue of the resultant superwettable cotton, the high-speed and high-efficiency in-situ purification of oily wastewater driven by negative pressure is successfully realized. More interestingly, benefitting from the photocatalytic property of TiO2, this resulting cotton can be also exploited for degrading water-soluble dyes to achieve water purification. In light of the unique predominance of the above-mentioned modified cotton, this newly developed economical strategy can promote the extensive development of multipurpose superwetting materials, providing tempting potential for the treatment of intricate oily wastewater.

Automated summary

This study successfully developed a functionalized material by decorating cotton with pH-sensitive carboxyl groups and photocatalytic titanium dioxide nanoparticles. The modified cotton can intelligently separate oil/water mixtures, purify oily wastewater, and degrade water-soluble dyes, showing promising potential for various applications.