Synthesis of novel WO₃.0·33H₂O microrods assembled discs with remarkable photocatalytic and electrochemical properties

The morphology of the materials is reputed to exhibit remarkable effect on the overall photocatalytic and electrochemical performance. In this study, novel WO₃.0·33H₂O microrods assembled discs (MADs) were successfully synthesized for the first time by simple hydrothermal method. The structure and morphological analysis of WO₃.0·33H₂O MADs was conducted by XRD and SEM/FESEM while its purity was confirmed by EDX spectroscopy. XRD presented the hexagonal crystal structure whereas the SEM/FESEM results revealed the microrods assembled disc type morphology with average diameter and width of the disc as 9.7 μm and 1.6 μm respectively. The vibrational modes were examined by FTIR and the existence of O-W-O, W = O bonds and O–H stretching modes confirmed the formation of WO₃.0·33H₂O MADs. The optical properties were studied by UV–Visible and PL spectroscopy which presented the bandgap energy of 2.3 eV while the blue PL emission at 434 nm was resulting from the band-to-band transition which also demonstrated the activation of MADs in visible region of spectrum. Finally, the photocatalytic activity of WO₃.0·33H₂O MADs was performed for the degradation of industrial wastewater which was about 2.3 times higher than that of commercially available WO₃. In addition, the electrochemical properties were also investigated using 0.5 M H₂SO₄ and the calculated specific capacitance was 798 Fg^-1 which was 3.8 times greater than commercial WO₃ (207 Fg^-1). These findings makes WO₃.0·33H₂O MADs as a potential candidate for visible light driven photocatalyst and as an electrode material for supercapacitors.