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

Abstract

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.

Tungsten-Based Catalysts for Environmental Applications

“…Preparation of WO 3 -graphene composite can be performed by different methods. Recent studies reported techniques such as the electrospinning technique to obtain a porous tungsten oxide nanoframework with graphene film [368]; a one-pot synthesis, first mixing sodium tungstate and nitric acid and then adding tetraphenylporphyrinn, graphene and citric acid (final calcination in the 350-550 • C temperature range) [369]; or a method based on pulsed laser ablation in liquid phase: WO 3 nanoparticles suspended in water were mixed with a suspension of monolayer graphene and irradiated for 30 min by the pulsed laser beam of 355 nm. During the laser irradiation, the photoinduced electrons in the WO 3 reduced graphene, and WO 3 nanoparticles were anchored on the graphene sheets [370].…”

Enhance Solar‐Light‐Driven Photocatalytic Degradation of Norfloxacin Aqueous Solution by RGO‐Based CdxZn1‐xS Alloy Composite with Band‐Gap Tuneability

“…Recently, two‐dimensional (2D) nanostructures have attracted increasing research interest in photocatalysis, energy generation and energy storage . The reduced graphene oxide (RGO) based semiconductor composite photocatalysts play an important role in the degradation of different organic water pollutants and water splitting . The synergistic effect of RGO and the attached semiconductor plays a crucial role in achieving high‐performance photocatalyst for the effective removal of aqueous organic pollutants .…”

“…The reduced graphene oxide (RGO) based semiconductor composite photocatalysts play an important role in the degradation of different organic water pollutants and water splitting . The synergistic effect of RGO and the attached semiconductor plays a crucial role in achieving high‐performance photocatalyst for the effective removal of aqueous organic pollutants . Due to the favorable matching of the conduction band of attached semiconductor with RGO's chemical potential facilitates the excited‐state electron transfer from the attached semiconductor to RGO sheets, which hinders the electron‐hole recombination probability and subsequently increases the photocatalytic activity of the composite.…”

“…Due to the favorable matching of the conduction band of attached semiconductor with RGO's chemical potential facilitates the excited‐state electron transfer from the attached semiconductor to RGO sheets, which hinders the electron‐hole recombination probability and subsequently increases the photocatalytic activity of the composite. Several efforts have been adopted to functionalize RGO with the photocatalysts to improve photocatalytic efficiency . To this end, RGO‐CdZnS has been widely investigated photocatalyst for the effective removal of organic dyes from the aqueous environment and H 2 ‐production from water splitting .…”

A photoredox catalysed Heck reactionviahole transfer from a Ru(ii)-bis(terpyridine) complex to graphene oxide

“…22,23 Over the last few years an increasing number of reports have described the successful application of graphene/graphene oxide as promotors in photocatalysis, 25 oen doped with nitrogen 26 or in combination with a semiconductor. [27][28][29][30][31] In addition, 3D cross-linked graphene materials have been used in redox catalytic applications 32 and functionalized graphene quantum dots have emerged for potential applications. [33][34][35][36] Recently, photocatalytic selective organic transformations [37][38][39][40][41] including homogenous photocatalyzed C-C cross-coupling reactions under visible-light have attracted much interest.…”