Photocatalytic conversion of MB dye using Co₃O₄ QDs‐Ag₂MoO₄ as an active heterojunction photocatalyst under visible light irradiation

Abstract

Herein, the preparation of Co 3 O 4 QDs-Ag 2 MoO 4 (AMO) heterojunction was reported by a facile hydrothermal method and characterized by physicochemical methods such as Fourier transformed infrared (FT-IR), X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), energydispersive X-ray spectroscopy (EDS), transmission electron microscopy (TEM), differential reflectance spectroscopy (DRS), photoluminescence spectroscopy (PL), and UV-Vis. The SEM images show that AMO particles and Co 3 O 4 QDs-AMO have a morphology of 3D-hexagons and nanosheets accumulated on the surface of 3D-hexagons with an average of 36 and 28 nm in size, respectively.The Co 3 O 4 QDs-AMO photocatalyst was used toward the conversion of methylene blue with a removal percentage of 91%, which is 15 times more than pure AMO. The higher photoactivity of Co 3 O 4 QDs-AMO heterojunction should be assigned to its lower charge recombination rate compared with pure AMO nanoparticles. This heterojunction photocatalyst was removed from the mixture reaction and reused five times without a considerable decline in activity. Furthermore, a postulated mechanism by the hydroxyl radical ( OH) path was proposed.

Improved decolorization of MB using CeCoO3/PbS heterojunction as a superior‐excellent photocatalyst

“…Different amounts of catalyst (0, 1, 3, 5, and 8 mg) were tested in the decolorization of MB reaction under specific conditions 4 . Because of the property of heterogeneous photocatalysis, the photo decolorization of MB boosts with increasing the amount of catalyst.…”

“…Different amounts of catalyst (0, 1, 3, 5, and 8 mg) were tested in the decolorization of MB reaction under specific conditions. 4 Because of the property of heterogeneous photocatalysis, the photo decolorization of MB boosts with increasing the amount of catalyst. It raises the active sites on the surface of the photocatalyst and the number of • OH, which is the main species of discoloration of MB solution.…”

“…This phenomenon is called photocatalysis, and it entails the catalyst absorbing photons, which stimulates the production of reactive species like hydroxyl radicals or superoxide ions 3 . These highly active species can oxidize organic dyes into harmless molecules like CO 2 and water 4 . Photocatalytic degradation offers several advantages, such as being a green and sustainable method as it utilizes solar or artificial light as an energy source 5 .…”

“…3 These highly active species can oxidize organic dyes into harmless molecules like CO 2 and water. 4 Photocatalytic degradation offers several advantages, such as being a green and sustainable method as it utilizes solar or artificial light as an energy source. 5 It can be applied to a wide range of pollutants, including organic compounds, dyes, pesticides, and even certain heavy metals.…”

High proficiency Ag/β-Ag2WO4/V3O4/g-C3N4 heterojunction photocatalyst for the actuation of C(OH)–H bond

“…In the last few years, Ag-based photocatalytic materials such as AgVO 3 , 17–19 Ag 2 CO 3 , 20–22 Ag 2 WO 4 , 23 Ag 3 PO 4 /Ag 2 MoO 4 , 24,25 Ag 2 CrO 4 –GO, 26 and Ag 3 PO 4 27–29 have attracted significant attention. Among the different crystallographic forms of Ag 2 WO 4 , β-Ag 2 WO 4 displays higher photoactivity than two others α-Ag 2 WO 4 and γ-Ag 2 WO 4 but the stability of it is less.…”