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Heterogeneous photocatalytic systems generally lack thermodynamic dependence on the degradation of organic pollutants in aqueous solution. Therefore, it is important to reveal the reasons for the inhibited surface kinetics but still be neglected. Herein, we reveal the mechanism that BiVO4 can't degrade organics although it is thermodynamically feasible. The surface solvation and formation of double layer (compact layer and diffuse layer) makes low-polarity organics far away from the surface of BiVO4. We found that the introduction of sulfite can solve this problem. Theory calculation illustrates that sulfite can enter into the compact layer because of its higher adsorption energy on BiVO4 and lower adiabatic ionization potential (AIP). Then, photogenerated holes initiate the chain transformation of sulfite and produce strong oxidizing species which can diffuse out to degrade organics. This paper provides an insight into the understand the effects of solid-liquid interface on heterogeneously photocatalytic degradation of organic pollutants. [ABSTRACT FROM AUTHOR]

Graphite carbon nitride (g-C3N4) is a promising photocatalyst for its high catalytic activity, low-cost and high-biosafety characteristics. Due to the complexity of underwater photochemical reaction conditions and the disadvantages of g-C3N4 itself such as low specific surface area, easy recombination of photogenerated electron–hole pairs and insufficient light absorption capacity, the application of g-C3N4 in the field of water purification is limited. For improving underwater photocatalytic performance of g-C3N4, a g-C3N4/carbon nanotubes (CNT-CN) composite photocatalyst with high specific surface area and enhanced light absorption capacity were prepared by in situ solvothermal method. Its photodegradation efficiency at different underwater transmission light was further studied. The results show that CNT has good compatibility with g-C3N4. g-C3N4 can grow in situ on the surface of CNT and form a stable composite structure. Moreover, its degradation efficiency under long-wavelength irradiation is improved significantly. The degradation rate of CNT-CN at 550-700 nm was about 3 times than that of g-C3N4. Furthermore, CNT-CN can maintain higher photocatalytic activity under water. At 40 cm depth where light intensity and ultraviolet spectra were attenuated 63.8% and 80.1%, respectively, the degradation rate of CNT-CN3 can still reach 3.49 times than that of g-C3N4. Based on this study, the introduction of CNT effectively promotes the electron–hole separation efficiency of g-C3N4, widens its spectral response range, and thus improves its underwater degradation efficiency. [ABSTRACT FROM AUTHOR]

Surface acid site regulation of photocatalysts is a promising strategy to improve their performance. Herein, surface acid sites of cadmium sulfide were rationally regulated by cerium doping, which resulted in significantly increased photocatalytic activity for tetracycline hydrochloride (TC-HCl) degradation. The generated Brønsted acid sites were verified to favor the adsorption of organic molecules because of their strong affinity. Meanwhile, Lewis acid sites acted as the active sites for C–C bond cleavage via a nucleophilic substitution process, which was testified by the Fukui function and electrostatic potential. Besides, Ce3+ doping suppressed the recombination of electron–hole pairs, which also boosted the performance of TC-HCl degradation. Moreover, the degradation pathway of TC-HCl was deduced based on theoretical calculations and HPLC-MS results. The toxicity of pollutants and intermediates was also evaluated. This work provided new insight into the rational design and preparation of highly efficient photocatalysts for environmental purification. [ABSTRACT FROM AUTHOR]

A series of boron carbon nitride–pyromellitic dianhydride (BCNPA) composites were successfully synthesized for the first time, where BCNPA3 exhibited the best adsorption and photodegradation performances for tetracycline (TC) under visible-light irradiation. 1H NMR characterization confirmed the fact that BCNPA3 was formed via the dehydration reaction between the OH groups in BCN and COOH groups in PA. Elemental N in BCNPA3 could capture protons and increase the pH of the TC solution from 3.73 to 6.80; consequently, TC changed from the positive state (pH 3.73) to the neutral state (pH 6.80). Subsequently, the adsorption capacity of BCNPA3 for TC increased from 66.24 mg g−1 (at pH 3.73) to 74.66 mg g−1 (at pH 6.80). This may be attributed to the fact that these captured protons can work as adsorption sites, too. Furthermore, the photodegradation efficiency of BCNPA3 for TC at pH 6.80 under visible-light irradiation was also higher than that at pH 3.73 (95% vs. 87%), because TC at pH 6.80 is less stable than that at pH 3.73. More interestingly, Cr(VI) could only be photoreduced into Cr(III) by BCNPA3 under visible-light irradiation when it coexisted with TC. This could be attributed to the fact that the photodegradation of TC increased the separation efficiency of the photoinduced electron and hole; consequently, the photoinduced electrons had sufficient time to reduce Cr(VI). Photoinduced ˙O2− and holes had the main contribution toward TC photodegradation by BCNPA3, while photoinduced electrons were responsible for Cr(VI) photoreduction. The adsorption and photodegradation performances of BCNPA3 for TC and Cr(VI) could be easily recovered under visible-light irradiation. [ABSTRACT FROM AUTHOR]

Herein, we present the preparation of nano-TiO2-silicone resin composite films by double liquid phase spray deposition. The films exhibit better adhesion stability and photocatalytic activity under a hydrodynamic erosion condition than conventional nano-TiO2 composite films. The TiO2 layer morphology and effective TiO2 coverage ratio (CR) were affected by the initial curing time (ICT) of the silicone resin, e.g., the increase in an ICT from 10 to 40 min resulted in a CR change from 79.1 to 98.7%. The surface morphology evolution of composite films was studied under a hydrodynamic erosion period of 4 weeks. Obtained results allowed the 4-week evolution to be divided into four stages (pitting, crack pregnant, banded stripping, and surface stripping periods), additionally revealed that the CR of all samples was remained above 65%. The photocatalytic activity of composite films before and after 4-week hydrodynamic erosion was evaluated by rhodamine B degradation experiments. The 4-week erosion only led to the decrease of the photodegradation efficiencies by less than 40% in all cases. Thus, the fabricated TiO2-silicone composite films demonstrated excellent durability and photocatalytic activity under the conditions of long-term hydrodynamic erosion, allowing one to conclude that this work paves the way to the fabrication of next-generation photocatalytic materials for industrial applications. [ABSTRACT FROM AUTHOR]

Ag-modified helical chiral TiO NFs (Ag@chiral TiO NFs) were fabricated and characterized by ultraviolet-visible absorption spectroscopy, scanning electron microscopy, and X-ray photoelectron spectroscopy. This novel material exhibited efficient photocatalytic activity for the degradation of 17α-ethinylestradiol (EE2) in water under visible light irradiation with an optimum size of deposited silver nanoparticles (Ag NPs) in the range of 12 ∼ 14 nm. The pseudo-first-order rate constant ( k) for EE2 photodegradation by Ag@chiral TiO NFs increased by up to a factor of 20.1 when compared with that of pure chiral TiO NFs. The high photocatalytic activity can be attributed to the interactions between helical chiral TiO NFs and surface plasmon resonance effect of Ag NPs. The new catalyst retains its photocatalytic activity at least up to five consecutive cycles. The results clearly demonstrate the feasibility of using Ag@chiral TiO NFs for the photocatalytic removal of EE2 and other endocrine-disrupting chemicals from water. [ABSTRACT FROM AUTHOR]

Abstract: Graphene–Bi2MoO6 (G–Bi2MoO6) hybrid photocatalysts were prepared by a simple one-step process in which the reduction of graphene oxide (GO) and the growth of Bi2MoO6 crystals occurred simultaneously. The material was characterized by X-ray diffraction, scanning electron microscopy, nitrogen adsorption–desorption isotherms, X-ray photoelectron spectroscopy, UV–vis diffuse reflectance spectroscopy and Raman spectroscopy. The photocatalytic activity was investigated by the degradation of reactive brilliant red dye X-3B. An increase in photocatalytic activity was observed for G–Bi2MoO6 hybrids compared with pure Bi2MoO6 under visible light. This improvement was attributed to the following two reasons: increased migration efficiency of photo-induced electrons and increased adsorption activity for dye molecules. A study of the effect of the amount of graphene on the photocatalytic activity showed that there was an optimum amount of 2.5% (initial GO weight). [Copyright &y& Elsevier]

Sediments exposed to sunlight can serve as an important source of dissolved organic carbon (DOC) and nutrients to overlying waters. However, the photochemical release processes of dissolved organic matter (DOM) from resuspended sediments and the characteristics of photoreleased DOM are not fully understood. In this study, excitation-emission matrix fluorescence combined with parallel factor analysis (EEMs-PARAFAC) was used to study the photochemical release of DOM qualitatively and quantitatively. The EEMs-PARAFAC demonstrated that the photoreleased DOM is dominated by humic-like substances, and the photorelease process could be consist of the photoproduction and photodegradation of DOM. The concurrent photodegradation may result in the underestimation of photoreleased DOM. Moreover, the significant increases in DOC content and fluorescence intensity of humic-like components along with increasing nitrate and ferric ion indicated that nitrate and ferric ion could facilitate the photoproduction of DOM through the photochemical produced hydroxyl radical. However, the decreases in DOC and fluorescence intensity were also observed at high concentration of nitrate and ferric ion, owing to the photodegradation of DOM by redundant hydroxyl radical. All of these results suggest that EEMs-PARAFAC is an effective and sensitive analytical technique for evaluating DOM photoreleased from suspended lake sediments and previous studies may underestimate photochemical release of DOM from sediments due to the overlook of the subsequently photodegradation of these released DOM. Thus, the photochemical release of DOM and its associated pollutants from suspended particles in shallow and eutrophic lakes should be more significant then should be paid more attention. Image 1 • Photorelease of DOM from sediment were well determined by fluorescence spectroscopy. • The photorelease and photodegradation of DOM occurred simultaneously. • NO 3 − and Fe3+ could promote the photorelease of DOM through photo-Fenton reactions. [ABSTRACT FROM AUTHOR]

Polyetherimide-graphitic carbon nitride (PEI- g -C 3 N 4 ) floating photocatalyst has been synthesized by using polyetherimide (PEI) as linker to bind graphitic carbon nitride (g-C 3 N 4 ) together. XRD and XPS analysis for PEI-g-C 3 N 4 show that the interaction between PEI and g-C 3 N 4 does not disturb the structure of g-C 3 N 4 . FTIR, TEM and theoretical results suggest that the long chain PEI binds g-C 3 N 4 particles together to form PEI-g-C 3 N 4 via hydrogen bonding interaction. Based on photodegradation results of methyl orange (MO), PEI can not photodegrade MO and just works as linker in PEI-g-C 3 N 4 , while the photodegradation performance of PEI-g-C 3 N 4 is from the contribution of g-C 3 N 4 . Total organic carbon (TOC) analysis show that nearly 47% organic carbon has been converted into inorganic carbon after photodegradation, suggesting that PEI-g-C 3 N 4 can destroy both N N bond and aromatic rings in MO under light irradiation. The photodegradation efficiency (91%) of MO by g-C 3 N 4 is higher than that (80%) by PEI-g-C 3 N 4 with stirring. But, the photodegradation efficiency (37%) of MO by g-C 3 N 4 is lower than that (55%) by PEI- g -C 3 N 4 without stirring. This is the advantage of floating photocatalyst with respect to the powder photocatalyst since the former can utilize more solar energy than the latter when stirring is not available. [ABSTRACT FROM AUTHOR]

In order to explore the influence of various carbon introduction on the morphology and photodegradation performance of C/g-C 3 N 4 composites, three kinds of different carbon materials: carbon nanotubes (CNT), graphene (GN) and carbon fibers (CF) were introduced to modify g-C 3 N 4 , and the morphologies, light absorption capacities and the underwater purifications of the composite photocatalysts were investigated. Results showed that the composites synthesized with different carbon substrates shows great differences in growth morphology. In addition, the introduction of various carbon sources also has a great impact on the physical and chemical properties of the composites. Compared with GN/g-C 3 N 4 and CF/g-C 3 N 4 , CNT/g-C 3 N 4 shows strong light absorption ability, especially in long-wavelength region (570–660 nm). To further study the difference of degradation ability of the composites in the underwater environment, the purification performance of modified g-C 3 N 4 at different water depths were carried out. The results show that under 40 cm of water, where the light intensity and ultra violet spectral are seriously attenuated, the purification efficiency of CNT/g-C 3 N 4 at 40 cm is 3.35 times than that of g-C 3 N 4. This work provides insight in the design of highly efficient metal-free photocatalysts for the environmental remediation. [Display omitted] • The effects of morphology difference on the degradation performance of C/g-C 3 N 4 composite photocatalysts were discussed. • The degradation efficiencies of C/g-C 3 N 4 under long wavelength irradiation were significantly enhanced. • The purification performances of C/g-C 3 N 4 over methyl orange at actual underwater transmission light were tested. • The experimental results are significance for the practical application of photocatalytic degradation. [ABSTRACT FROM AUTHOR]

Photocatalytic technology is an attractive and promising approach for nitenpyram degradation; however, how to ensure the carrier separation efficiency and catalytic sites exposure is still great challenges. In this study, we construct CdS@MoS 2 (CM) nanohybrids with a 3D hierarchical configuration to enhance the separation and transfer efficiency of the photo-induced electron by a covalent-anion-driven self-assembly method. The vertical orientation of MoS 2 ultrathin nanosheets not only provides a large specific surface area for the oxidation and reduction reactions but also enables the active edge sites of MoS 2 to be maximally exposed. As a result, this structure drastically facilitates the exposure of the catalytic active region and the performance of the carrier transfer and injection into photocatalytic degradation for nitenpyram (NTP). The optimal CdS–MoS 2 has an impressive and stable NTP removal efficiency with a high reaction rate constant up to 0.078 min−1, which is 3.25 times higher than that of pure cadmium sulfide. The photocatalytic degradation mechanism and degradation pathway of NTP were presented by synthesizing the results of experimental analysis and density flooding theory (DFT) calculations. In further, for the first time, the cytotoxicity and genotoxicity of NTP on moving bed biofilm reactors (MBBRs) was disclosed and a continuous photocatalytic wastewater pretreatment device based on the CM is proposed for the stable biological nitrogen removal activity of MBBRs, which can degrade more than 80% NTP per hour. • The composite photocatalyst was constructed by covalent-anion-driven self-assembly method. • Compared with pure CdS, the photogenerated carrier separation efficiency of CdS@MoS 2 (CM) was enhanced by 4.8 times. • The composite exhibited significantly activity for NTP degradation. • The degradation pathways were precisely predicted based on experimental analysis and DFT calculations. [ABSTRACT FROM AUTHOR]

A series of bismuth oxychloride (BiOCl)–graphene (GR) nanocomposites were prepared by a solvothermal method. The obtained samples were characterized by scanning electron microscopy, X-ray diffraction, transmission electron microscopy, ultraviolet–vis diffuse reflectance spectrum, Brunauer–Emmett–Teller surface areas, and Fourier transform infrared spectrophotometer. Results showed that BiOCl in the composites exhibits a morphology of square-like nanoplates wrapped in GR sheets. The amount of GR influenced the crystalline, optical absorption ability, specific surface area, and adsorption property of the nanocomposites. High photocatalytic activity was observed for the degradation of the heteropolyaromatic dye methylene blue under ultraviolet irradiation. Additionally, the results indicated that there was an optimum GR amount of 30% for obtaining the highest photocatalytic activity. [ABSTRACT FROM AUTHOR]

Abstract: N,Ce-codoped titania hollow spheres were prepared using carbon spheres as template and using N,Ce-codoped titania nanoparticles as building blocks. The N,Ce-codoped titania nanoparticles were synthesized at low temperature. The prepared hollow spheres were characterized by X-ray diffraction (XRD), transmission electron microscope (TEM), X-ray photoelectron spectroscopy (XPS) and UV–Vis diffuse reflectance spectrum (DRS). The effect of N and Ce content on the physical structure and photocatalytic properties of the as-prepared hollow sphere samples was investigated. The mechanism of photocatalytic degradation of dyes under visible light irradiation was also discussed. [Copyright &y& Elsevier]

Abstract: Ce-doped titania hollow spheres were prepared using carbon spheres as template and Ce-doped titania nanoparticles as building blocks. The Ce-doped titania nanoparticles were synthesized at low temperature. The prepared hollow spheres were characterized by X-ray diffraction (XRD), transmission electron microscope (TEM), X-ray photoelectron spectroscopy (XPS) and UV–vis diffuse reflectance spectrum (DRS). The effect of Ce content on the physical structure and photocatalytic properties of doped titania hollow sphere samples was investigated. Results showed that there was an optimal Ce-doped content (4%) for the photocatalytic activity of X-3B degradation. The apparent rate constant of the best one was almost 31 times as that of P25 titania. The mechanism of photocatalytic degradation of dyes under visible light irradiation was also discussed. [Copyright &y& Elsevier]

A series of boron nitride-pyromellitic dianhydride composites have been successfully synthesized by calcinating the mixtures of boron nitride (BN) and pyromellitic dianhydride (PA) at 350 °C, in which the composite (BNPA2) has the largest adsorption quantity (65.1 mg/g) for rhodamine B (RhB) and the best photo-removal efficiency for RhB under visible light irradiation. 1H NMR characterizations for BN, PA and BNPA2 suggest that this composite is formed via the reaction between the OH groups in BN and PA. BNPA2 can also adsorb neutral red (NR), methyl orange (MO), tetracycline (TC) and atrazine (AT). NR and MO can be photo-removed by BNPA2 under visible light irradiation. Colorless TC and AT can also be degraded by BNPA2 under visible light irradiation, suggesting that BNPA2 is visible light responsible photocatalyst. BNPA2 has the highest photo-removal efficiency for the cationic RhB and NR, followed by the anionic MO. This is from that BNPA2 has negative surface. When anionic MO mixes with cationic RhB (or NR) together, BNPA2 prefers to remove cationic RhB (or NR) from the mixture solution under visible light irradiation and the removal efficiency of anionic MO by BNPA2 is also increased. Thus, electrostatic interactions between dyes and BNPA2 as well as between dyes play significant role in the removal process. •O2− makes a main contribution for this photo-removal of these aromatic pollutants (dyes, TC and AT) by BNPA2 under visible light irradiation. Furthermore, the removal performance of BNPA2 for RhB, TC and AT can be effectively regenerated by visible light irradiation. • Boron Nitride-Pyromellitic Dianhydride composite (BNPA2) is first time synthesized with BN and PA as precursors. • BNPA2 can remove organic pollutants (dyes and atrazine) via adsorption and photodegradation. • BNPA2 is visible light responsive photocatalyst and the photocatalytic performance of BN is from sensitization. • Electrostatic attraction between dyes and BNPA2 play significant role during the removal process of dyes. • Visible light irradiation can regenerate the removal performance of BNPA2 for dyes. [ABSTRACT FROM AUTHOR]

Fe3+ mediating photodegradation of organic pollutants has attracted extensive attention in the field of environment remediation. However, most works focused on low concentration (C Fe <1 mM) system under UV light, in which hydroxyl radicals (•OH) is the main radical for pollutants degradation. In this work, we discover a new mechanism of visible light induced (VLI) symmetry-breaking charge separation for pollutants degradation in high-concentration Fe3+ system (HC-Fe3+, C Fe >1 mM). The formed binuclear hydrolyzed Fe3+ species ([(H 2 O) 4 Fe(μ-OH) 2 Fe(H 2 O) 4 ]4+) in HC-Fe3+ system significantly broadens the optical absorption range and induces to the generation of Fe(Ⅳ), thus leading to highly efficient degradation of organic pollutants. In addition, a logarithmic correlation between the adiabatic ionization potential (AIP) and the reaction rate constant (k) of organics is obtained. The new findings further broaden the knowledge on the generation of Fe(Ⅳ) and the photo-induced charge transfer mechanism of binuclear hydrolyzed Fe3+ species in the VLIHC-Fe3+ system. [Display omitted] ● Fe(Ⅳ) was generated in visible light induced high-concentration Fe3+ system. ● Photo-induced symmetry-breaking charge separation of Fe3+ dimer was revealed. ● Red-shift of absorption edge of Fe3+ solution due to the generation of Fe3+ dimer. ● Structure-activity relationship for organic degradation in Fe3+ system was found. [ABSTRACT FROM AUTHOR]

The interaction and electron transfer between pollutant molecules and photocatalysts are critical to the degradation process but has been rare studied. In the present contribution, donor–acceptor (D-A) type graphitic carbon nitride (g-C 3 N 4) with expanded π-conjugated system are elaborately prepared. The removal efficiency of bisphenol A (a typical endocrine disruptor) by the optimal sample is 2.9 times as that of pure g-C 3 N 4. Based on the experimental results and DFT calculation, it is found that the formed charge transport channels in D-A g-C 3 N 4 substantially promote the spatial separation and transfer efficiency of photogenerated charges. Besides, the expanded π-conjugated system improves light absorption ability, enhances the π-π interactions between catalysts and pollutant molecules (facilitating the adsorption and electron transfer of pollutant). This study provides a new idea for photocatalysis to achieve efficient environmental remediation, that is, while modifying the catalyst, further considering the adsorption and electron transfer of pollutants in the degradation process. [Display omitted] • D-A g-C 3 N 4 with expanded π-conjugated system was simply prepared. • The improved separation and transfer efficiency of charge carriers in D-A g-C 3 N 4. • Expanded π-conjugated system promotes the adsorption and electron transfer of BPA. The interaction and electron transfer between pollutant molecules and photocatalysts are critical to the degradation process but has been rarely studied. In the present contribution, donor–acceptor (D-A) type graphitic carbon nitride (g-C 3 N 4) with expanded π-conjugated system are elaborately prepared. The removal efficiency of bisphenol A (a typical endocrine disruptor) by the optimal sample is 2.9 times as that of pure g-C 3 N 4. Based on the experimental results and DFT calculation, it is found that the formed charge transfer channels in D-A g-C 3 N 4 substantially promote the spatial separation and transfer efficiency of photogenerated charges. Besides, the expanded π-conjugated system improves light absorption ability, enhances the π-π interactions between catalysts and pollutant molecules (facilitating the adsorption and electron transfer). This study provides a new idea for photocatalysis to achieve efficient environmental remediation, that is the adsorption and electron transfer of pollutants in the degradation process should be further considered while modifying the photocatalysts. [ABSTRACT FROM AUTHOR]

Uncovering the interaction between photocatalyst and reaction substrate as well as subsequent electron transfer process is critical to achieve high-performance photodegradation of pollutants. Herein, based on the reduced density gradient (RDG) method, we visualize the simulation of the π-π interactions between photocatalyst (g-C 3 N 4) and pollutant molecule (flumequine, FLU). Results revealed that π-π interactions between g-C 3 N 4 and FLU favor electrons delivery, resulting in enhanced charge separation efficiency and direct hole oxidation of FLU. Moreover, it is found that the charge transfer rate is determined by the valence band (VB) level of g-C 3 N 4 and E HOMO of FLU, of which the deeper VB position of g-C 3 N 4 favors faster charge transfer, leading to further enhancement in photocatalytic degradation rate of FLU. Additionally, the possible degradation pathways of FLU were proposed by theoretical calculation and the determined intermediates. Our work afforded a new insight into pollutants degradation and the rational design of highly efficient photocatalysts. [Display omitted] • π-π interactions between g-C 3 N 4 and flumequine were established based on the reduced density gradient (RDG) method. • Interface relationship and electrons transfer mode were investigated at the molecular level experimentally and theoretically. • Intermolecular π-π interactions formed channels for electron delivery which induced to enhanced FLU degradation efficiency. • A positive correlation between the rate constant and the difference value of E VB (g-C 3 N 4) and E HOMO (FLU vs. NHE) was found. • The possible degradation pathways of pollutants were proposed by theoretical calculation and the determined intermediates. [ABSTRACT FROM AUTHOR]

[Display omitted] • The dual Z-scheme photocatalysts with phase junction WO 3 and CdS were fabricated. • The 75CW has the best photocatalytic rate of imidacloprid degradation. • The Fukui indexes were exploited to predict reactive sites. • The reliable degradation pathways of imidacloprid were proposed. The construction of dual Z-scheme photocatalysts is an effective way to promote the separation and migration of electrons-holes as well as retain their high redox abilities. Herein, a distinctive dual Z-scheme photocatalyst based on phase junction WO 3 and CdS (CW) was successfully fabricated via hydrothermal method and in-situ precipitation process. The as-prepared materials showed the advantages of both phase junction and dual Z-scheme mechanism (promoted utilization of carriers and improved redox potential). As a result, the k app value of 75CW (0.05237 min−1) was 29.8 times that of phase junction WO 3 (0.00176 min−1) and 2.9 times that of CdS (0.01799 min−1) in terms of imidacloprid (IMD) degradation. Trapping experiment and electron spin resonance (ESR) proved the dual Z-scheme mechanism, the key to significantly improve photocatalytic degradation efficiency of WO 3 /CdS nanocomposites. Combined the analysis of liquid chromatography-mass spectrometry (LC-MS) with density functional theory (DFT) calculation, rational degradation pathways of IMD were put forward in detail. This work is excepted to provide new horizons for the construction of dual Z-scheme system with phase junction and the photodegradation of IMD. [ABSTRACT FROM AUTHOR]

Abstract: The photocatalytic degradation kinetics of rhodamine B (RhB) by TiO2-coated activated carbon (TiO2/AC) catalyst under different reaction conditions (light intensity, TiO2 content in TiO2/AC and initial content of contamination) was elucidated by modeling. The kinetics of Rhb photodegradation was found to follow the first-order rate law and could be described in terms of a modified Langmuir–Hinshelwood model. The value of the apparent rate constant k app was proposed on the basis of intrinsic element reactions, such as light intensity, reaction intermediates and the photo-induced hole (h±) formation. The apparent rate constant k app first increased with increasing TiO2 content of the TiO2/AC catalyst and then decreased. The optimal value of the TiO2 content could be obtained through the model; the apparent rate constant was linear with respect to the square of the intensity. The validity of the model was also proved with other researchers’ results. [ABSTRACT FROM AUTHOR]