Layered Na2W4O13 and its cation/anion doped analogues for the treatment of polluted water

Abstract Tungsten based materials have attracted substantial attention due to their potential applications in environmental remediation in the form of degrading organic pollutants to less harmful byproducts. In continuation of search for better photocatalytic materials, layered tungstate (Na 2 W 4 O 13 ), have been chosen and aimed to enhance its photocatalytic activity by doping Sn 2+ and N 3− its lattice. Na 2 W 4 O 13 (NaWO) was synthesized by sol-gel method. The divalent tin and trivalent nitrogen doped NaWO were prepared by ion exchange and solid state methods, respectively. All the materials were investigated by XRD, FESEM-EDS, XPS, and UV–visible diffuse reflectance techniques. The bandgap energy of parent NaWO and Sn 2+ /N 3− doped NaWO was evaluated from their diffused reflectance spectral profiles. The photocatalytic activity of these samples was evaluated by photodegradation of rhodamine B (RhB) and 4-chlorophenol (4-cp). The mechanistic degradation pathway of RhB was studied using radical quenchers. The removal of Pb 2+ from an aqueous solution of Pb(NO 3 ) 2 using NaWO was discussed.