In-Situ Synthesis of Tetraphenylporphyrin/Tungsten (VI) Oxide/Reduced Graphene Oxide (TPP/WO₃/RGO) Nanocomposite for Visible Light Photocatalytic Degradation of Acid Blue 25

Environmental pollution is regarded as a major concern and photocatalysis has been used successfully to combat discharges of recalcitrant pollutants. In this study, meso tetraphenylporphyrin (TPP), tungsten (VI) oxide and reduced graphene oxide nanocomposite materials were prepared by in situ method and calcined at different temperatures. The catalysts impact was evaluated for the degradation of acid blue 25 (AB25) under visible light irradiation. The as-prepared composite materials were characterised for morphological and crystalline structural properties using SEM, Raman, FTIR, TGA, BET and XRD techniques. UV-Vis and PL absorption studies obtained a band gap energy of 2.14 eV which showed its ability to absorb light in the visible region. The nanocomposite exhibited spherically shaped particles of monoclinic WO₃ when using 20 mg TPP and calcination temperature of 350 °C for 4 hours. The highest degradation efficiency of 85% on 20 ppm AB25 as per UV/Vis and TOC results, was obtained for the photocatalyst calcined at 350 °C for 4 hours. The high degradation efficiency can be ascribed to the visible light absorbing nature of the composite and high separation rate of photogenerated charge carriers. This nanocomposite can be a suitable candidate for treatment of other dyestuff in textile effluents.