A novel sodium polyacrylate grafted activated carbon was produced by using gamma radiation to increase the number of functional groups on the surface. After irradiation the capacity for nickel adsorption was studied and found to have increased from 44.1 to 55.7 mg g(-1). X-ray absorption spectroscopy showed that the adsorbed nickel on activated carbon and irradiation-grafted activated carbon was coordinated with 6 oxygen atoms at 2.04-2.06 angstrom. It is proposed that this grafting technique could be applied to other adsorbents to increase the efficiency of metal adsorption. (C) 2009 Elsevier B.V. All rights reserved.