Facile fabrication of sodium carboxymethyl cellulose/reduced graphene oxide composite hydrogel and its application for Pb(II) removal

Abstract

Abstract The sodium carboxymethyl cellulose/reduced graphene oxide (rGO‐CMC) composite hydrogel was fabricated via environmental friendly one‐step hydrothermal reduction method. The morphology, pore structure and surface properties of the as‐prepared sample were characterized by scanning electron microscopy, Brunauer–Emmett–Teller surface area measurement and zeta potential analyser, respectively. To investigate the adsorption behaviour of rGO‐CMC for Pb(II), effects of contact time, temperature, initial concentration and pH were studied in detail. The rGO‐CMC composite before and after adsorption of Pb(II) was analysed by Fourier transform infrared spectroscopy and X‐ray photoelectron spectroscopy to further explore adsorption mechanism. Compared with rGO, the adsorption capacities of rGO‐CMC‐3 composite for heavy metals including Pb(II), Cu(II), Ni(II), Mn(II), Co(II) were increased to 156.85, 35.70, 21.40, 20.85 and 15.80 mg g−1, respectively. In addition, the rGO‐CMC composite formed a complete aerogel after freeze‐drying, which confirms its great potential as an easily separable adsorbent to remove heavy metals in aqueous solutions.