Enhancement of H₂O₂ Decomposition by the Co-catalytic Effect of WS₂ on the Fenton Reaction for the Synchronous Reduction of Cr(VI) and Remediation of Phenol

Abstract

The greatest problem in the Fe(II)/HO Fenton reaction is the low production of ·OH owing to the inefficient Fe(III)/Fe(II) cycle and the low decomposition efficiency of HO (<30%). Herein, we report a new discovery regarding the significant co-catalytic effect of WS on the decomposition of HO in a photoassisted Fe(II)/HO Fenton system. With the help of WS co-catalytic effect, the HO decomposition efficiency can be increased from 22.9% to 60.1%, such that minimal concentrations of HO (0.4 mmol/L) and Fe (0.14 mmol/L) are necessary for the standard Fenton reaction. Interestingly, the co-catalytic Fenton strategy can be applied to the simultaneous oxidation of phenol (10 mg/L) and reduction of Cr(VI) (40 mg/L), and the corresponding degradation and reduction rates can reach up to 80.9% and 90.9%, respectively, which are much higher than the conventional Fenton reaction (52.0% and 31.0%). We found that the expose reductive W active sites on the surface of WS can greatly accelerate the rate-limiting step of Fe/Fe conversion, which plays the key role in the decomposition of HO and the reduction of Cr(VI). Our discovery represents a breakthrough in the field of inorganic catalyzing AOPs and greatly advances the practical utility of this method for environmental applications.

Fast and Long‐Lasting Iron(III) Reduction by Boron Toward Green and Accelerated Fenton Chemistry

“…k (COH/l-AA) = 1.1 10 10 m À1 s À1 , k (COH/ HA) = 0.5-9.5 10 9 m À1 s À1 ), giving rise to al ow mineralization efficiency of the target contaminants. [9b,10] Lately,m etal sulfides such as WS 2 and MoS 2 with reductive metallic sites were used to promote Fe II regeneration and enhance Fenton oxidation, however, the coupled systems required light irradiation and might cause secondary contamination due to the leached metal ions and generation of toxic H 2 S. [11] Boron is am etalloid element and locates between the nonmetallic carbon and metallic beryllium in the periodic table.Electron-deficient boron atoms bond with each other to form icosahedral B 12 monomers via electron-sharing B À B bonds,c onsequently building the bulk architecture via twocenter-and three-center-two-electron shared BÀBbonds into manifold interlinked polyhedron. [12] It has been reported that diboron compounds with BÀBb onds can serve as electron donors and contribute reductive sites to the surface of TiO 2 , ZnO,SnO 2 ,Nb 2 O 5 ,and In 2 O 3 via strong interfacial coupling, which affords 1000 times greater visible light response to enhance the performance of perovskite solar cells.…”

Fast and Long‐Lasting Iron(III) Reduction by Boron Toward Green and Accelerated Fenton Chemistry

“…The dissimilar enhancement is attributed to the specific ROS generated in the three systems [Eq. (1), (10), (11)], [4,14] because DEP is more readily to react with COH (3.7 10 9 m À1 s À1 )c ompared to SO 4 C À (6.3 10 7 m À1 s À1 ). [15] Fe II þ HSO 5…”

Facile Synthesis of Co3O4 Nanoparticle-Functionalized Mesoporous SiO2 for Catalytic Degradation of Methylene Blue from Aqueous Solutions

“…Various types of biological and physical methods have been utilized to remove organic compounds from industrial wastewater. Biological treatment is a cost-effective technology of removing organic dye from wastewater but suffers from some drawbacks, such as easy inactivation, owing to the toxic biological effects from organic chemicals [3]. Ion exchange or adsorption is also a common and effective means of removing organic pollutions.…”

“…Ion exchange or adsorption is also a common and effective means of removing organic pollutions. However, post-treatments are usually required to regenerate the resins/adsorbents and prevent secondary contamination [3]. Thus, AOPs, Fenton and Fenton-like reactions have been widely studied due to their high efficiency in generating hydroxyl radicals for decontamination of recalcitrant organic pollutants.…”