A new graphene/geopolymer nanocomposite for degradation of dye wastewater

A novel graphene/geopolymer nanocomposite was firstly synthesized by using two-dimension graphene (GR) and alkali-activated granulated blast furnace slag-based geopolymer (ASG), and used to degrade simulation dye effluents. Diffuse reflectance UV–Vis spectrum indicated that the maximum absorption wavelength of the nanocomposite (GR/ASG) is red-shift to the visible region. The pore diameter distribution results of the GR/ASG1 sample showed that at least 89.59% of pore volume centralized on the region of 2–50 nm. The photocatalytic degradation efficiencies of samples for methyl violet dye is in the order of GR/ASG1 > GR/ASG2 > ASG under the irradiation of UV. The GR/ASG1 photocatalyst exhibited the highest degradation efficiency and approached to 91.16% for 110 min. The photocatalytic degradation reaction belongs to the second-order reaction kinetics.