Ultralight, compressive and superhydrophobic methyltriethoxysilane-modified graphene aerogels for recyclable and selective organic pollutants adsorption from water

Physical adsorption is considered to be a more effective, green and economical way to remove organic pollutants. However, it still remains a challenge to simultaneously obtain the adsorbent materials with low density, high adsorption capacity and selectivity, and superior elasticity to satisfy multiple reusing. Herein, we developed a one-step solvothermal co-assembly method to produce methyltriethoxysilane (MTES)-modified graphene aerogels (MGAs). The MGA possesses low density, high porosity, fantastic elasticity and high specific surface area. It can be completely recovered under 1,000 cyclic compression tests of 90 % high strain. The compressive and ultralight MGA could be used as adsorbent for various organic liquids with high capacity (290–620 g/g), exceeding most of previously reported absorption materials. The sorbed organic pollutants could be recovered through mechanical absorption-squeezing procedure. The MGA retains about 97% original absorption capacity after 20th cycles. Hydrophobic methyl groups of MTES were successfully grafted onto graphene oxide (GO), which solidified the frameworks of graphene aerogel and made the MGA a good candidate for selective oil/water separation. Consequently, this novel manufacturing method and excellent performance make the MGA exhibits remarkable application potential for water treatment.