Superior photocatalytic activity of Cu doped NiWO4 for efficient degradation of benzene in air even under visible radiation

Abstract We effectively used Cu dopant to improve photocatalytic performance of NiWO 4 to remove benzene in air. The obtained experimental result indicated that photocatalytic performance of the prepared Cu-NiWO 4 materials were greater than that of the pure NiWO 4 . This was because Cu effectively acted as novel dopant, which not only affected valence band (VB) top and conduction band (CB) bottom of NiWO 4 but also formed a medium energy level between CB and VB of the NiWO 4 to decrease its energy band gap and electron-hole recombination rate. Hence, the photocatalyst produced large available charge amounts (electron and hole) initiating photocatalysis for degradation of gaseous benzene. The optimized Cu/Ni mole ratio for maximum improving photocatalytic performance of NiWO 4 was 3%. The maximum benzene removal efficiency and its mineralization via visible light photocatalysis of the 3Cu-NiWO 4 were 93.7 and 96.5 %, respectively. The synthesized Cu-NiWO 4 photocatalyst also presented great stability in benzene removal processes.