Promising Materials for Photocatalysis‐Self‐Fenton System: Properties, Modifications, and Applications

Abstract

Photocatalysis‐self‐Fenton system (PSFs), which integrates photocatalysis with Fenton technology, is investigated thoroughly in wastewater treatment due to the virtues of no addition of H2O2 and accelerated circulation of Fe2+/Fe3+. Several kinds of materials that mainly include metal‐free graphite carbon nitride (g‐C3N4), metal oxides (Fe3O4), and metal sulfide (CdS, FeS2) have demonstrated extensive development potential. Nevertheless, most of the developed catalysts are unable to satisfy the requirements of PSFs. Therefore, a comprehensive review committed to the materials and modification methods in PSFs is put forward. First, the concrete mechanism of PSFs from two aspects of photocatalysis and Fenton reaction is discussed. Second, the properties, modifications (morphology modulation, heterojunction construction as well as doping), and applications (contaminants degradation and disinfection) of the promising catalysts are emphasized. Finally, the novel directions for future research in PSFs are looked forward to. This review opens up a new horizon for enhancing the practical application of PSFs in future.

Highly Efficient FeIII‐initiated Self‐cycled Fenton System in Piezo‐catalytic Process for Organic Pollutants Degradation

“…Recently, Fe II regeneration and H 2 O 2 production are successfully coupled into one redox system over semiconductor catalysis, under which the Fenton reaction can sustainably proceed, so-called self-cycled Fenton. [6] For example, in the carbon nitride photocatalytic self-Fenton system created by Wu et al, [7] photo-electrons simultaneously enabled the H 2 O 2 production and Fe II regeneration, greatly boosting the degradation of pollutants. Wei et al [8] developed an efficient piezo-catalytic system of in situ piezogeneration and utilization of H 2 O 2 over Fe/BiVO 4 , significantly promoting the production of powerful oxidizing hydroxyl radicals ( * OH).…”

“…Recently, Fe II regeneration and H 2 O 2 production are successfully coupled into one redox system over semiconductor catalysis, under which the Fenton reaction can sustainably proceed, so‐called self‐cycled Fenton [6] . For example, in the carbon nitride photocatalytic self‐Fenton system created by Wu et al., [7] photo‐electrons simultaneously enabled the H 2 O 2 production and Fe II regeneration, greatly boosting the degradation of pollutants.…”

A Minireview: The Mechanism of H2O2 Photoproduction by Graphitic Carbon Nitride

“…Nowadays, some researchers focus on the preparation of modified g-C 3 N 4 , [25,26] while others are immersed in the process and mechanism of H 2 O 2 photoproduction. [27,28] However, the understanding of the mechanism is far below the development of the photocatalyst and hinders the further development and application.…”

Multi-heteroatom-doping promotes molecular oxygen activation on polymeric carbon nitride for simultaneous generation of H2O2 and degradation of oxcarbazepine

“…Considering that the photocatalytic properties of these charge transfer processes are related to the lifetime and concentration of the carriers that can reach the catalyst surface, great efforts have been made in the separation of photoinduced electron–hole pairs, especially in nanostructure design and band structure specifications. 26…”

“…Considering that the photocatalytic properties of these charge transfer processes are related to the lifetime and concentration of the carriers that can reach the catalyst surface, great efforts have been made in the separation of photoinduced electronhole pairs, especially in nanostructure design and band structure specifications. 26 In particular, elemental doping 27 and defect control 28 are the most widely used methods to improve the photocatalytic activity of PCN. For instance, PCN that has been doped with alkali metals (K + or Na + ) displays a wide spectrum of light absorption and high separation efficiency of charge.…”