Synthesis of WO3·H2O spherical particles for efficient photocatalytic properties under visible light source

Tungstic acid (WO3·H2O) spherical particles were fabricated by economical solvothermal rout. Crystallinity, structural properties and elemental composition of fabricated material were characterized by XRD and EDX. Morphological structure was explored by using FEMSEM, and the results indicated that the as-prepared material has spherical shape with average size up to 500 nm. The existence of OWO stretching and υ(O-H) vibration modes in FTIR spectra confirm the formation of WO3·H2O spherical particles. Further, UV–VIS-NIR and PL spectra were studied which suggested that the as-prepared sample has band gap of 2.5 eV that was favorable for photocatalytic process. Finally, the as-synthesized material was utilized for the degradation of RhB and it demonstrated remarkable photo-degradation performance with k = 0.0244 min−1 that was about 4.3 times greater than that of bulk WO3·H2O. The possible mechanism for the photocatalytic process has been discussed by finding the valence and conduction band potentials of the photocatalyst. Keywords: Tungstic acid, Spherical particles, Rhodamine B