▎ 摘　　要

Graphene oxide (GO) was functionalized with alpha cyclodextrin (alpha CD) through a covalent bond to form GO-alpha CD nanocomposites (NC). GO-alpha CD NC was further modified with polypyrrole (PPY) to afford an advanced GO-alpha CD-PPY NC for the removal of highly toxic Cr(VI) from water. The prepared GO-alpha CD-PPY NCs were successfully characterised with AT-FTIR, FE-SEM, HR-TEM, BET and XRD techniques. Adsorption experiments were performed in batch mode to determine optimum conditions that include temperature, pH, concentration of Cr(VI) and contact time. It was deduced from the experiments that the adsorption of Cr(VI) by the GO-alpha CD-PPY NC is pH and temperature dependent, where optimum adsorption was achieved at pH 2 and it increased with increasing temperature. The adsorption kinetics followed the pseudo-second-order model and the adsorption isotherms fitted well to the Langmuir isotherm model with maximum adsorption capacities ranging from 606.06 to 666.67 mg/g. Effect of co-existing ions studies revealed that cations and anions had no significant effect on the adsorption of Cr(VI). Desorption studies also illustrated that the NC can be re-used up to 3 cycles. (C) 2015 Elsevier B.V. All rights reserved.