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In the field of electrocatalysis, single-atomic-layer tungsten, copper, and cobalt oxide on CeO 2 , ethylene diamine (ED) and reduced graphene oxide (rGO) supported materials shows tremendous potential. Despite the enormous interest in single metal atom oxide (SMAO) catalysts, it is still very difficult to directly convert readily available bulk metal oxide into single atom oxide. It is crucial and tough to create high performance materials for the oxygen evolution reaction (OER) in an alkaline environment. Herein, a single tungsten, copper and cobalt atom oxide (SMAO) anchored on the CeO 2 atomic layer and overall components deposited on the rGO (rGO-ED-CeO 2 -WCuCo) is prepared through a one-pot sonication technique. The presence of SMAO is identified by high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM) imaging. The electrocatalytic performance of final rGO-ED-CeO 2 -WCuCo-30 nanocomposite for the OER in 1 M KOH electrolyte is evidenced by providing low overpotential of 283 mV at 10 mA cm -2 . The Tafel slope for OER using rGO-ED-CeO 2 -WCuCo-30 electrocatalysts is 57.03 mV dec -1 . The electrocatalytic activity of rGO-ED-CeO 2 -WCuCo-30 nanocomposites for OER was noticeably increased when compared to bare CeO 2 nanorods (401 mV), rGO-ED-CeO 2 -WCo-30 (345 mV), rGO-ED-CeO 2 -WCu-30 (340 mV) and rGO-ED-CeO 2 -WCuCo-20 (321 mV) samples., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

An effective catalyst for the removal of antibiotic pollutants which severely impact water bodies and the environment is most favorable. In this study, g-C 3 N 4 (gCN) and nitrogen-doped Bi 2 MoO 6 (gCN-NBM) heterostructures are developed using a solvothermal process with enhanced photocatalytic degradation of tetracycline (TC) pollutants under visible-light irradiation. The experimental results confirm that nitrogen-doped Bi 2 MoO 6 (NBM) nanomaterials were dispersed on the gCN surface, and a close combination of NBM and gCN leads to the efficient photocatalytic performance of TC. The photocatalytic efficiency of the heterostructure catalysts is four-fold higher than those of the pristine Bi 2 MoO 6 catalysts owing to the excellent photogenerated charge separation and reduced recombination rate. Photocurrent measurements and electrochemical impedance spectra results disclose that the prepared heterostructure catalysts exhibit efficient photo-induced charge transfer. The electron spin resonance spectra and quenching experiments results reveal that superoxide radicals ( . O 2 - ) play a major role in TC degradation. This study presents a promising approach for designing efficient visible-light photocatalysts for environmental remediation applications., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Intense studies are being carried out on single atom catalysts that exhibit remarkable activity and selectivity. To enhance their catalytic abilities, one must have a thorough understanding of the properties of the single metal atom active site and its dynamics in the working state. Herein, we report single metal atom oxide (SMAO) (metal: W/Cu) anchored on TiO 2 -rGO nanomaterials (SMAO-ED-TiO 2 -rGO) by simple sonication process. It is efficient for the electrocatalytic hydrogen evolution reaction (HER), oxygen evolution reaction (OER) and photocatalytic degradation of pharmaceutical pollutant. The uniform dispersion of the tungsten/copper metal atom oxide over a TiO 2 -rGO materials is detected by high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM). The SMAO-ED-TiO 2 -rGO nanocatalyst has shown impressive HER/OER activity with an overpotential of 121/295 mV at (-)10 mA cm -2 current density and the low Tafel slope of 96/60.3 mV dec -1 in 1 M KOH solution. Further, SMAO-ED-TiO 2 -rGO nanocatalyst was used for the photocatalytic degradation of ciprofloxacin (CF). After 60 min of UV light irradiation, the SMAO-ED-TiO 2 -rGO nanocatalyst efficiently photodegraded 98.5% of CF while retaining its activity for five cycles. Superoxide radicals (O 2 •- ) are found to be the main reactive species required in the photodegradation of CF, according to scavenger study of the SMAO-ED-TiO 2 -rGO nanocatalyst for CF degradation., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

In this work, MoS 2 /Mg(OH) 2 /BiVO 4 ternary hybrid photocatalyst was synthesized by sonicated precursor mixture to the hydrothermal procedure to generate a highly efficient solar light-induced and simply recyclable photocatalyst. The obtained hybrid was confirmed by the characteristic peaks of MoS 2 /Mg(OH) 2 /BiVO 4 observed in X-ray diffraction (14.31°/18.62°/28.18°), infrared spectra (465/445/679 cm -1 ), ultraviolet-visible spectra (636/683/639 nm) studies, and the band-gap narrowing (2.62/2.44/2.25 eV). The morphological structure of MoS 2 (rod), Mg(OH) 2 (particles), and BiVO 4 (random aggregates) were turned into MoS 2 /Mg(OH) 2 /BiVO 4 hierarchical nanosheets that coexisted with particles. The photodegradation experiments of the photocatalysts were assessed by using Congo Red (CR), Malachite Green (MG) and Textile Industry Effluent (TIE) as the model pollutant under direct sunlight. The photocatalytic efficiency of the hybrids was noticeably 2.1 to 2.3 times higher than that of the individual components. Photocurrent response test indicate that MoS 2 /Mg(OH) 2 /BiVO 4 ternary hybrid nanocomposites photocatalysts had a more effective electron/hole pair separation than individual and binary composite photocatalysts. The mechanism of photodegradation of MoS 2 /Mg(OH) 2 /BiVO 4 ternary hybrid photocatalysts was investigated and discussed., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022. Published by Elsevier Ltd.)

The development of recyclable catalysts with effective properties and stable reusability is great importance for the removal of different types of pollutants in wastewater. Herein, we have synthesized Polyvinylidene fluoride (PVDF) polymer and mixed-phase 1T/2H MoS 2 for immobilizing the sonocatalyst material. Techniques such as FESEM, XRD, FTIR, XPS, and UV-vis spectra have been used for analyzing the structural, and morphological properties. The formation of a 1T/2H mixed phase in MoS 2 has been revealed by XRD and XPS analysis. Consequently, the sonocatalytic performance of the nanocomposite membrane was investigated through ciprofloxacin (CIP) and organic pollutants (Rhodamine B (RhB)). As a result, MoS 2 /PVDF (PM4) nanocomposite membrane exhibited a superior sonocatalytic activity with 94.37% and 84.37% of RhB and CIP degradation efficiency with pseudo-first-order kinetic constant (k) of 0.0187 min -1 , and 0.0044 min -1 . The sonocatalytic property of the nanocomposite membrane is related to 1T/2H mixed-phase and PVDF. Additionally, the metallic based 1T phase MoS 2 helps to promote electrons and holes and reduce the recombination rate. Moreover, it promotes the generation of more hydroxy radicals ( . OH), and superoxide radicals (∙O 2 - ) play a significant role in sonocatalytic degradation of RhB pollutants. Thus, the improved sonocatalytic degradation of 1T/2H MoS 2 /PVDF composite membrane exhibited its application in real-time wastewater treatment., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

Developing cost-effective and highly effective visible-light-driven photocatalysts for decomposition of organic contaminants has been deliberated as an important and viable strategy for environmental remediation. Herein, MoS 2 /Bi 2 WO 6 heterostructure photocatalysts were fabricated with excellent visible light absorption performance and efficient electron/hole (e - /h + ) separation efficacy. As-prepared all photocatalysts were systematically characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), transmission electron microscopy (TEM), high resolution TEM, X-ray photoelectron spectroscopy (XPS). Although photocatalytic experiments were examined by UV-vis diffuse reflectance spectroscopy (UV-vis DRS), photoluminescence spectroscopy (PL), and transient photocurrent (I-t). Among all the photocatalysts, that synthesized by using the components 10 mg of Bi 2 WO 6 with 100 mg of MoS 2 (denoted as MSBW-10), displayed high photocatalytic performance (96.31%) for tetracycline (TC) under visible light irradiation within 90 min. The kinetic rate constant of the MSBW-10 heterostructure was 5.51 and 6.71 times higher than those of MoS 2 and Bi 2 WO 6 , respectively. Further, radical trapping experiments revealed that ˙OH radicals and holes were the predominant reactive species involved in the photocatalytic course. The recycle tests revealed the stability of the photocatalyst, which exhibited 91.85% TC removal efficacy without obvious decay even after the fourth cycle. Furthermore, the type-II MoS 2 /Bi 2 WO 6 heterostructure photocatalyst exhibited a slighter band gap with energy band alignments and enhanced visible-light absorption, separation of charge carriers, and good oxidation/reduction capacities. These deeper insights and synergetic effects can afford a new approach for flourishing novel heterostructure photocatalysts., (Copyright © 2022 Elsevier Ltd. All rights reserved.)