Photocatalytic performance of starch-supported cobalt-doped WO3 nanoparticles for sunlight driven catalytic removal of Rhodamine- B and crystal violet dye

In this work, Cobalt-doped WO₃ (Co-doped WO₃) samples were prepared by co-precipitation method with starch assistance by adjusting the concentration of dopant. The optical, chemical, structural, and photocatalytic activity of prepared samples were analyzed with different dopant concentrations. X-ray diffraction (XRD) technique was utilized to study the structural behavior of synthesized samples. The morphology of the samples was revealed by FESEM images. Raman and FTIR spectral analysis further confirmed the structural aspects. With an increase in dopant concentration, it has been found that bandgap energy falls up to 2.62 eV while Urbach energy rises to 378 meV for 10 wt% Co-WO₃. The dye degradation using photocatalysis with the help of prepared samples has been assessed in the presence of sunlight with H₂O₂. The maximum photocatalytic activity was discovered for 10 wt% Co-WO₃ which degraded almost 98 % of RhB in 120 min and 96 % of CV in 105 min. The enhanced photocatalytic activity of 10 wt% Co-WO₃ NPs demonstrates its potential use in the treatment of wastewater.