Solar-induced photocatalytic degradation of textile dyes using composite of indium oxide and silver vanadate

In the present study, the synthesized samples indium oxide (In 2 O 3 ), silver vanadate (Ag 3 VO 4 ), and composite (In 2 O 3 /Ag 3 VO 4 ) are prepared by using co-precipitation method. These samples showed a very effective photocatalytic response for the degradation of a dye methylene blue (MB) in the presence of sunlight. The physical properties of samples are characterized by XRD, scanning electron microscopy (SEM), FTIR, and ultraviolet (UV) spectroscopy. The structure analysis and crystalline size of prepared samples were examined by XRD. Debye Scherrer’s formula had been used to calculate the crystalline size and its value is 19.1 nm of In 2 O 3 , 10.8 nm of Ag 3 VO 4 , and 1.65 nm of In 2 O 3 /Ag 3 VO 4 . FTIR absorption spectroscopy was carried out in the range of 500–4000 cm −1 to verify the synthesized material’s structural properties. FTIR spectrum also provides the information about the material’s functional groups. The morphology of indium oxide, silver vanadate, and composite was analyzed by SEM. The calculated grain sizes of indium oxide, silver vanadate, and In 2 O 3 /Ag 3 VO 4 composite are 0.13, 0.72, and 0.56 µm, respectively. The optical properties indicate a small band gap for composite, which is 1.65 eV and showed strong absorption for sunlight. The photocatalytic degradation of MB was performed by using prepared catalysts in the presence of sunlight at wavelength 300–900 nm by UV spectroscopy. Indium oxide degraded MB to 76.5% and silver vanadate degraded MB to 71%, while the composite degraded MB to 85.5%. The results of UV spectroscopy showed that the composite is very effective in photocatalytic degradation MB dye.