Visible-light photoelectrocatalysis/H₂O₂ synergistic degradation of organic pollutants by a magnetic Fe₃O₄@SiO₂@mesoporous TiO₂ catalyst-loaded photoelectrode

Abstract

A visible-light PEC/H2O2 synergistic system based on Fe3O4@SiO2@mesoporous TiO2 photocatalysts was constructed. Reaction mechanisms during PEC/H2O2 coupling system were elucidated.

Bifunctional Fenton-like catalyst enabling oxidative and reductive removal of contaminants synergically in chemical reagent-free aerated solution

“…Iron oxide, being one of the most abundant and cheap oxide materials, is widely used as a catalyst for oxidation (particularly the Fenton reaction [1]) and reduction reactions in environmental remediation processes. The Fenton reaction can be further enhanced by the supply of additional energy such as light and electricity and can be classified as photo-Fenton [2][3][4], electro-Fenton [5][6][7][8], or photoelectro-Fenton reaction [9][10][11][12] depending on the external energy source. These Fenton systems need H 2 O 2 and ferrous ions (Fe 2+ ) or in-situ generation of H 2 O 2 through O 2 reduction with the subsequent decomposition of H 2 O 2 by Fenton catalysts to generate highly reactive • OH for the degradation of organic pollutants [13].…”

“…The electrochemically in-situ generated H 2 O 2 via oxygen reduction reaction (ORR) was immediately decomposed by the Fe species in the material. In a photoelectrochemical system that needs the input of both light and electricity, the degradation of organic contaminants was significantly enhanced using Fe 3 O 4 @-SiO 2 @mesoporous TiO 2 photoelectrode in the presence of H 2 O 2 [12]. However, most of the previous studies on the iron-based oxidative degradation processes required an excess amount of chemical oxidants and/or external energy input to initiate the reactions, which increases the operating cost.…”

Rational Construction of MOF-Derived Porous ZnTiO3/TiO2 Heterostructured Photocatalysts with Remarkable Photocatalytic Performance

“…In order to overcome these challenges, doping with metal/nonmetal elements, or compositing TiO 2 with metal, nonmetal, and other semiconductors are effective ways to improve the photocatalytic activity. − Constructing heterojunctions is regarded as an effective way to improve the utilization efficiency of solar light and suppress the recombination of electrons/hole pairs by building an internal electric field at the heterojunction interface. − The perovskite-typed materials (ABO 3 ) have become much more popular due to their superior photocatalytic activity under both UV and visible light irradiation. − Their structure is very stable and flexible by varying the composition of A and B sites to optimize the electronic and catalytic properties. − Among them, zinc titanate (ZnTiO 3 ) is one of the most promising photocatalysts to be applied in the degradation of pollutants and water splitting, which is considered as an ideal candidate to couple with TiO 2 for improving the photocatalytic performance of TiO 2 via creation of heterojunctions.…”

Unlocking the Potential of Nanobubbles: Achieving Exceptional Gas Efficiency in Electrogeneration of Hydrogen Peroxide

“…[1][2][3] Moreover, H 2 O 2 has been increasingly adopted in advanced water treatment technologies, including H 2 O 2 /UV, H 2 O 2 /titanium dioxide (TiO 2 ), H 2 O 2 /persulfate (PS), and Fenton technologies. [4][5][6][7][8][9][10][11] However, ≈95% of large-scale production of H 2 O 2 through the anthraquinone oxidation process is an energy-intensive method involving harmful chemicals and by-products. [12][13][14][15] In addition, this process is mainly used to produce a high concentration of H 2 O 2 (35%, 50%, and 70% by weight).…”