One‐step synthesis of a WO₃‐CuS nanosheet heterojunction with enhanced photocatalytic performance for methylene blue degradation and Cr(VI) reduction

Abstract

BACKGROUND: The photocatalytic activity of a pristine semiconductor is unsatisfactory due to the rapid recombination of photogenerated electrons and holes. Constructing composite photocatalysts has proven to be an effective method to suppress electron-hole recombination. The composites composed of two materials usually are synthesized through a two-step process. However, in this work, a simple one-step solvothermal method employing an homogeneous reaction system was adopted to synthesize a tungsten trioxide (WO 3 )-copper sulfide (CuS) nanosheet heterojunction with enhanced photocatalytic properties. RESULTS: The formation of the WO 3 -CuS heterojunction was confirmed by X-ray diffraction, transmission electron microscopy, energy-dispersive X-ray and X-ray photoelectron spectroscopy analysis. The composites showed improved visible light harvesting ability, and enhanced photoelectric and photocatalytic properties compared with pure WO 3 . The optimized composite displayed a photocurrent almost five-fold greater than the sum of the photocurrents of WO 3 and CuS, and had superior performance for methylene blue (MB) degradation and hexavalent chromium [Cr(VI)] reduction. The MB degradation and Cr(VI) reduction efficiencies were both improved when they co-existed in the photocatalytic system. Interferential ions Cl − and NO 3− were much less effective in the degradation of MB than in the reduction of Cr(VI). CONCLUSIONS: Improved photocatalytic activity was achieved after coupling CuS with WO 3 , due to the enhanced visible light absorption and efficient electron-hole separation. Photogenerated holes were found to be the dominant reactive species in the MB photodegradation process. A synergistic effect existed between MB degradation and Cr(VI) reduction. Interferential ions Cl − and NO 3 − had much greater effect on Cr(VI) reduction than MB degradation. Evaluation of the interference effects of ionsInorganic ions, such as chloride (Cl − ) and nitrate (NO 3 − ) ions, are found widely in natural water sources, and may interfere with the photocatalysis process. Ion interference experiments were conducted herein to investigate the photocatalytic activity of WO 3 -CuS in the presence of Cl − or NO 3 − ions. As shown in Fig. 10, Cl − and NO 3 − had little effect on MB degradation, whereas they J Chem Technol Biotechnol 2020; 95: 665-674

Albumin-assembled copper-bismuth bimetallic sulfide bioactive nanosphere as an amplifier of oxidative stress for enhanced radio-chemodynamic combination therapy

“…The binding energies at 932.3 and 952.2 eV were ascribed to Cu 2p 3/2 and Cu 2p 1/2 ( Fig. 2h ), which corresponded to the standard values of Cu 2+ in Cu–S bond [ 35 ]. There was no difference between the binding energies of Cu 2p in BBCD and BBC ( Supplementary Fig.…”

Highly efficient removal of 2,4‐dichlorophenal over a novel dual Z‐scheme heterojunction of Bi7O9I3/BiOIO3/g‐C3N4 under visible‐light irradiation: performance and mechanism

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Photocatalytic Degradation of Tobacco Tar Using CsPbBr3 Quantum Dots Modified Bi2WO6 Composite Photocatalyst

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