Cross-Linked Carbon Nanotube Adsorbents for Water Treatment: Tuning the Sorption Capacity through Chemical Functionalization

The development of carbon-based membrane adsorbent materials for water treatment has become a hot topic in recent years. Among them, carbon nanotubes (CNTs) are promising materials because of its large surface area, high aspect ratio, great chemical reactivity, and low cost. In this work, free-standing CNT adsorbents are fabricated from chemically cross-linked single-walled CNTs. We have demonstrated that by controlling the degree of cross-linking, the nanostructure, porous features, and specific surface area of the resulting materials can be tuned, in turn allowing the control of the adsorption capacities and the improvement of the adsorption performance. The cross-linked CNT adsorbents exhibit a notably selective sorption ability and good recyclability for removal of organics and oils from contaminated water.