Rare earth ions (La3+, Nd3+) substituted cobalt–strontium spinel ferrites for photocatalytic degradation of textile dyes

Abstract

Abstract In the industrial sector, productive and effective treatment of toxic dye-based color pollutants is a key issue. Lanthanum and neodymium substituted cobalt–strontium (Co–Sr) spinel ferrite (Co0.5Sr0.5RExFe2-xO4, x = 0.00 and 0.06) catalysts were synthesized and used to degrade Congo red and rhodamine B dyes from an aqueous solution mixture in this study. For this specific purpose, RE3+ ions substituted Co–Sr spinel ferrite nanoparticles with photocatalytic degradation ability were prepared through sol–gel method. The degradation of CR and RhB in recently synthesized nanoferrites was also examined. SEM and XRD were used to characterize the prepared samples. The optical band gap values of synthesized spinel ferrites were examined with the help of Tauc plots by using UV-visible absorption. It was determined that the energy bandgap ranged from 2.91 to 2.52 eV. For Co0.5Sr0.5Fe2O4, Co0.5Sr0.5La0.06Fe1.94O4, and Co0.5Sr0.5Nd0.06Fe1.94O4 nanoferrites, the rates of CR and RhB dye degradation were 73–90% and 45–85%, respectively, at pH 5–7. The kinetics models successfully described the degradation reaction as pseudo-first-order kinetics. It was, therefore, concluded that the prepared samples can be used as effective photocatalysts in order to eliminate hazardous pollutants present in wastewater.