Enhanced photocatalytic conversion of organic dyes using CeCoO₃/MoS₂ heterojunction as a highly effective visible‐light‐driven photocatalyst

Abstract

The CeCoO3/MoS2 heterojunction was successfully prepared through the hydrothermal method. The synthesized heterojunction structure was characterized by various techniques and applied to the conversion of methylene blue (MB) under irradiation of visible light. To characterize the new heterojunction structure, Fourier transformed infrared (FT‐IR), field emission scanning electron microscope (FE‐SEM), energy‐dispersive X‐ray spectroscopy (EDXS), X‐ray diffraction (XRD), photoluminescence spectroscopy (PL), differential reflectance spectroscopy (DRS), and transmission electron microscopy (TEM) analyses were used. The FE‐SEM images illustrated the successful deposition of MoS2 flower‐like on the surface of CeCoO3 perovskite with 46 nm as an average size. The influence of the amount of catalyst, temperature, pH, and electron acceptor were investigated. By CeCoO3/MoS2 heterostructures photocatalyst, the conversion rate of MB reached 98% within 20 min, whereas by CeCoO3 perovskite no significant conversion was observed in MB. The higher photocatalytic performance of CeCoO3/MoS2 heterostructures is assigned to their lower charge recombination compared to CeCoO3 perovskite. Moreover, the photocatalytic mechanism and recycling experiments of CeCoO3/MoS2 heterostructures are discussed in detail. The CeCoO3/MoS2 heterostructures are thus promising photocatalysts for the cleanup of polluted water.

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

“…The PL spectrum has a main role in determining the rate of charge separation in materials owing to the intensity of the emission resulting from charge separation. 55 High intensity of emission displays a faster charge recombination rate, which causes to decrease in the optical performance. 56 To consider the amount of electron–hole separation within all samples, the PL analysis was measured.…”

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

“…However, increasing temperature assists fine adsorption of reactants and accordingly improves charge recombination 35 . But at high temperatures, the electron‐hole recombination rate will expand 36,37 …”

“…35 But at high temperatures, the electronhole recombination rate will expand. 36,37 Studying the performance of catalysts toward the removal of dyes at different pH values is notable. The photocatalytic performance was examined at different pH ranges from 3 to 9 for 10 ppm at optimized conditions (Figure 4c).…”

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

“…As shown in Figure 6b, PbS as a semiconductor has a bandgap of 3.50 eV, and the bandgap energy for the CeCoO 3 /PbS nanocomposite was measured to be 2.77 eV, whereas CeCoO 3 has a bandgap of 1.29 eV. 28 To determine the bandgap of these samples, a method based on plotting the amount of absorption against the wavelength of light (λ) to light radiation (αhv) 2 was used, and according to Figure 6a, the samples performed well under UV regions. 10 To better understand the performance of nanocomposite photocatalysts in terms of recombination rate, it was evaluated through luminescence spectrum (PL) analysis.…”

“…Because of its good photocatalytic activity, cerium cobalt oxide perovskite is suitable for photocatalytic reactions in various chemical processes. 28 Also, as a semiconductor with suitable electronic and optical properties, PbS is used in the field of photocatalysis. 29 In these systems, the absorption of light by PbS leads to the excitation of electrons, after which chemical reactions begin on the surface of the photocatalyst.…”