Applied Catalysis B: Environmental, Vol.199, 412-423, 2016
Removal of Cr(VI) by 3D TiO2-graphene hydrogel via adsorption enriched with photocatalytic reduction
A novel method for removing Cr(VI) from aqueous solutions used a TiO2-graphene hydrogel with three-dimensional (3D) network structure. Graphene is capable of non-porous surface adsorption and pi-pi interaction adsorption. The combination between graphene and TiO2 nanospheres promoted photo induced charge transport and separation, thereby facilitating photocatalytic reduction of Cr(VI). For TiO2-rGH, the synergy of adsorption and photocatalysis played an important role in removing Cr(VI) from aqueous solutions. The TiO2-rGH material exhibited superb adsorption-photocatalysis performance, removing 100% Cr(VI) from a solution containing (5mg/L) within 30 min under UV irradiation. Under continuous flow conditions, the adsorption-photocatalytie activity of TiO2-rGH was well maintained and the Cr(VI)-removing percentage was kept at 100% for a prolonged period until the breakthrough point was reached. (C) 2016 Elsevier B.V. All rights reserved.