University of Vienna scientists have designed a composite material that is highly efficient at removing organic pollutants from water. The team achieved this with a nanoporous, ultrathin covalent organic framework (COF) fixed on graphene.
The material is reusable
COFs have a very porous structure besides being low density and light weight. Porous materials can deposit a particularly large number of molecules on surfaces during adsorption, as they have a much larger total surface area for the same volume than a non-porous material.
Industrial wastewater contains high levels of pollutants. Organic dyes, which are one of them, are generally highly soluble in water, do not decompose and have a carcinogenic effect. The researchers focused on dye molecules measuring 0.8 to 1.6 nanometers in size by varying the COF to allow it to selectively trap organic dye molecules.
The team was able to create tiny sponges with precisely sized and shaped pores in the nanometer range and a negative surface charge that can attract positively charged target molecules.
Although the sponge was developed, there was a problem that the inner pores of the material often became dysfunctional due to the clogging of the pores on the outer edge. To solve this problem, the researchers were able to produce COF on a graphene sheet.
To ultimately ensure the material’s maximum capacity to retain organic dye molecules, the team placed a two-nanometer-thick layer of COF over a single-atom graphene layer.
Developed a copper nanowire spray that makes surfaces antimicrobial
The researchers state that the material they developed does not require much graphene and can be reused as a filter after cleaning from contaminants, which will reduce the cost.
5502
