Synthesis, characterization and UV-A light photocatalytic activity of 20 wt%SrO–CuBi2O4 composite

A novel nanoscale powder 20 wt%SrO–CuBi2O4 has been successfully synthesized for the first time by ion exchange through doping Sr(NO3)2 into CuBi2O4 matrix and characterized using TG/DTA, XRD, EDX, SEM and electrical measurements. The as-prepared 20 wt%SrO–CuBi2O4 composite exhibit much higher photocatalytic activity than 20 wt%SrO–CuBi2O4 synthesized via physical process and pure phase CuBi2O4 under UV-A light irradiation (λ = 365 nm) in the course of the photocatalytic redox activity of Congo red (CR). Maximum degradation was achieved within 220 min of irradiation time under UV-A light as a result of 97.22% of photocatalytic efficiency of CR. The mechanisms of the enhancement of photocatalytic activity of the nanocomposite photocatalyst will be discussed by the p–n heterojunction principle (charge separation and photochemical diode models) and the valance band theory. The pure nanocomposite systems have been also reported for a comparative purpose.