Graphdiyne Filter for Decontaminating Lead-Ion-Polluted Water

Abstract

The decontamination of water polluted with heavy metal ions is of worldwide concern. Among various treatment approaches to remove metal ions from water, adsorption is regarded as an efficient method, and a variety of materials have been applied as adsorbents for the removal of metal ions from polluted water. Recently, carbon nanomaterials have been examined as alternative adsorbents due to their high specific surface areas, high removal efficiency, and strong interactions with metal ions. Graphdiyne, a new kind of carbon allotrope composed of sp- and sp2-hybridized carbon atoms, has attracted great interest due to its impressive properties. Graphdiyne is considered to be a promising candidate for the adsorption of heavy metal ions as the acetylenic links in graphdiyne strongly interact with metal ions. Herein, graphdiyne is used as an adsorbent to remove lead ions from water. The interaction between lead ions and graphdiyne is explored by X-ray photoelectron spectroscopy and Raman spectroscopy. The maximum adsorption capacity calculated by the Langmuir isotherm model is 470.5 mg g−1. Graphdiyne is also synthesized on copper foam and used as a filter to eliminate lead ions from water. The filter shows high performance with a removal efficiency of 99.6% and can be recovered through treatment with acidic solution.