A facile synthesis of metal vanadate incorporated with metal oxide/rare earth metal oxide composite for photocatalytic application

Abstract

In this work (Ag2O/BiVO4) binary and (Ag2O/BiVO4/Eu2O3) ternary heterojunction photo-catalysts have been synthesized through a hydrothermal technique for the purpose of photocatalytic degradation of hazardous dyes. The facile synthesized composites of (Ag2O/BiVO4) and (Ag2O/BiVO4/Eu2O3)have been prepared using a hydrothermal process. The synthesized composites used to degrade the Methylene blue and Congo-red dyes under sunlight. The X-ray diffraction confirms the crystalline structure of synthesized composites. The calculated crystalline sizes for (Ag2O/BiVO4) and (Ag2O/BiVO4/Eu2O3) are 9.9 nm and 2.84 nm respectively. The morphology of samples has been analyzed by SEM while the absorption spectrum and bonding of molecules were observed using FTIR in the range of 600–4000 cm−1. The elemental percentage of synthesized material is determined by using EDX spectroscopy and UV spectroscopy used to study optical properties. Using Tauc plot calculated band gap of (Ag2O/BiVO4)is 1.84 eV and (Ag2O/BiVO4/Eu2O3) is 1.65 eV. The degradation efficiency of composites(Ag2O/BiVO4) (Ag2O/BiVO4/Eu2O3) towards a dye MB is 38% and 41% respectively, while these composites were found to degrade the dye CR 82% and 99%respectively in the exposure of sunlight. Both synthesized composites showed excellent %age degradation toward acidic dye (CR). The outcomes of synthesized composites indicates that suitable optical absorption, better segregation of charge carries and reduction of electron-hole recombination these factor effectively contribute to enhance photocatalytic activity towards acidic dye CR.

Keywords

• Dye degradation
• Metal oxide
• Photocatalysis
• Rare earth
• Optical properties