Construction of Z-Scheme Ag₂MoO₄/ZnWO₄ Heterojunctions for Photocatalytically Removing Pollutants

Abstract

Facilitation of the photocarrier separation is a crucial strategy for developing highly efficient photocatalysts in eliminating environmental pollutants. Herein we have developed a new kind of Ag 2 MoO 4 /ZnWO 4 (AMO/ZWO) composite photocatalysts with a Z-scheme mechanism by anchoring AMO nanoparticles onto ZWO nanorods. Multiple characterization methodologies and density functional theory (DFT) calculations were employed to study the performances of the AMO/ZWO heterojunctions as well as the underlying photocatalytic mechanism. Simulated-sunlight-driven photodegradation experiments for removing methylene blue (MB) demonstrates that the 8%AMO/ZWO heterojunction can photocatalytically remove 99.8% of MB within 60 min, and the reaction rate constant is obtained as 0.10199 min −1 , which is enhanced by 6.8 (or 4.9) times when compared with that of pure ZWO (or AMO). On the base of the experimental results and DFT calculations, the enhanced photocatalytic mechanism of the AMO/ZWO heterojunctions was revealed to be the efficient separation of photocarriers via a Z-scheme transfer process. In addition, photodegradion of various organic pollutants over 8%AMO/ZWO was further compared and aimed at incorporating it into industrial application in pollutant removal.

Constructing hollow core–shell Z-scheme heterojunction CdS@CoTiO3 nanorods for enhancing the photocatalytic degradation of 2,4-DCP and TC

“…5a), implying the lowest recombination rate of photogenerated carriers. 56 Moreover, the lower charge-transfer resistance in the CdS@CoTiO 3 hybrid was also confirmed by the smaller high-frequency semicircle in the electrochemical impedance spectroscopy results (EIS, Fig. 5b).…”

Nanostructured Bi3+-Modified Ferrites: Magnetically Separable and Recyclable Catalysts for Sustainable Water Resource Management through Dye Degradation and Nitrophenol Reduction

“…Therefore, developing innovative and efficient treatment methods for eliminating dye contaminants in wastewater remains a pressing challenge for the scientific community. In this field, various techniques have been devised such as electrochemical processes, coagulation, membrane filtering, chemical oxidation, biodegradation, adsorption, and photocatalysis to eliminate organic dyes and other pollutants from wastewater. − However, heterogeneous photocatalysis is a well-established approach in this field. − This methodology involves the employment of advanced oxidation processes, which are dependent on the generation of highly reactive species such as hydroxyl radicals (•OH), in order to enhance the oxidation of a diverse range of organic pollutants in a nonselective manner . In the industrial production of chemicals like dyes, insecticides, explosives, etc., nitrophenols are created both as intermediates and final products.…”

Photoactive Fe3O4@Fe2O3 Synthesized from Industrial Iron Oxide Dust for Fenton-Free Degradation of Multiple Organic Dyes

“…Concerning water contaminants, industrial effluents are released from carpet, paper, textile, distillery, leather, and printing in large amounts and contains a lot of toxic organic dyes. , In general, these dyes are nonbiodegradable and possess high aqueous solubility and cause several health issues, such as cancer, respiratory illness, mutagenesis, loss of immunity, and allergic reactions . For degrading the organic contaminates, presently the process of photodegradation involving the use of ultraviolet, visible, and sunlight is in demand. − Generally photoactive materials individually or in the presence of cocatalyst produce reactive oxygen species (ROS) from water, which reacted with organic or inorganic contaminants of wastewater, and produce the usable treated wastewater. ,− …”