Development of graphene aerogels with high strength and ultrahigh adsorption capacity for gas purification

Abstract

Indoor gaseous pollutants pose a great threat to human health, graphene aerogel (GA) has attracted more and more attention due to its high adsorption performance. However, the increase of the adsorption capacity together with high strength for long time and repeat using is still a challenge. In this study, a novel silica modification method was proposed to modify graphene aerogels with high strength and ultrahigh adsorption capability. Apart from its high adsorption capacity for liquid toluene, the adsorption capability to benzene, an indoor pollutant gas, was increased to 809.51 mg/g, which is higher than pure graphene aerogel and other carbon-based adsorbents such as graphene, activated carbon and single-wall carbon nanotubes. The enhanced adsorption performance is due to two reasons in addition to the electrostatic interactions. On one hand, tetraethyl orthosilicate (TEOS) could help to modify the pore structure of aerogel, reducing its average pore diameter and increasing its BET specific surface area. On the other hand, the addition of TEOS could help to improve the hydrophobicity of aerogel. The selective adsorption character of graphene aerogels to benzene/toluene binary system in the breakthrough experiment confirmed that the prepared graphene aerogels could also be used in the field of separation of multicomponent indoor pollutant gases.

Keywords

• Graphene aerogel
• Silicon dioxide
• Adsorption capability
• Selective adsorption