Graphitic carbon nitride/metal-organic framework composite functionalized cotton for efficient oil-water separation and dye degradation

Developing materials with low cost, simple preparation process and versatility remains a challenge to solve the problems of marine oil spills and organic dye pollution. In this work, graphitic carbon nitride/metal-organic framework was synthesized by a simple hydrothermal method. And through a simple soaking method, the surface of cotton was modified to prepare superhydrophobic cotton with photocatalytic ability. The modified cotton exhibits an excellent superhydrophobic angle (153.05 +/- 2 degrees), and can sorb oil more than 10 times the mass of its own. After nine replicate oil (dichloromethane)-water separation, the separation rate is still above 99%. Oilwater separation can be achieved in 0 degrees C water, acidic and alkaline conditions. It is worth mentioning that cotton can separate micro-nano-scale water droplets from water-in-oil (toluene, castor oil, et.) emulsions. In addition, the cotton was immersed in ethanol for hydrophilic conversion and placed in 25 mg/mL Eriochrome Black T. When the sorbent was saturated, the degradation reached 90% after 5 min of light in the presence of H2O2.

Automated summary

In this study, graphitic carbon nitride/metal-organic framework material was synthesized through a simple hydrothermal method, and cotton was modified using a simple soaking method to prepare superhydrophobic cotton with photocatalytic ability. The modified cotton exhibited an excellent superhydrophobic angle and could sorb oil more than 10 times its own mass. The cotton material could achieve oil-water separation in various conditions and was able to separate micro-nano-scale water droplets from water-in-oil emulsions. Additionally, the cotton showed high efficiency in the degradation of Eriochrome Black T under light irradiation.