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In this paper, three-dimensional TiO2 nanoflowers (NFs) were prepared by a facile hydrothermal method, and Ag3PO4 was grown in situ following alkali treatment to design and synthesize a Ag3PO4/OH/TiO2 catalyst with excellent photocatalytic activity under visible light. The test results show that the photocatalytic degradation performance of TiO2 NFs after alkali treatment and Ag3PO4 loading is significantly improved. This is because the alkali treatment and the introduction of Ag3PO4 can provide a large amount of –OH, which can be converted to ˙OH under UV irradiation, followed by an increase in the number of active radicals to enhance the photocatalytic degradation performance. Meanwhile, the introduction of Ag3PO4 can effectively improve the light absorption ability of the photocatalyst. Moreover, the in situ growth of Ag3PO4 on TiO2 NFs can construct a high-quality Ag3PO4/TiO2 heterojunction to promote the charge separation and transport. Therefore, the degradation rate of Ag3PO4/OH/TiO2 can reach 90% after 30 min for degrading 3 mg L−1 RhB under visible light. The Ag3PO4/OH/TiO2 photocatalyst designed in the present work provides a new tool for the degradation of organic dyes. [ABSTRACT FROM AUTHOR]

Bismuth oxybromide (BiOBr) nanoflowers were anchored onto kaolinite nanosheets via a calcination method. Assisted by characterization methods including XRD, SEM, and XPS, the microstructures of photocatalysts were comparatively investigated. The findings revealed a close integration of BiOBr nanoflowers with kaolinite, resulting in a gradual phase transition and augmented surface oxygen. Furthermore, the photocatalytic performance was assessed by investigating the degradation of organic dyes under visible light irradiation. Notably, the experimental results demonstrated that the degradation efficiencies of BiOBr/kaolinite composites were higher than that of pure BiOBr. The ⋅O2− was proven to be the major active radical in the photocatalytic process. This study presents a straightforward approach for fabricating BiOBr‐based photocatalysts, showcasing their enhanced performance in organic dye degradation under visible light. [ABSTRACT FROM AUTHOR]

Remediation of organic dyes from wastewater in textile industries is a big challenge to decreasing water pollution. This study was aimed at the preparation of ZnO nanoparticles (NPs) and their application as a photocatalyst for the degradation of methylene blue (MB), sunfix red (SR) and real textile wastewater (RTW) under both UV and visible irradiations. The ZnO NPs were synthesized with a green Thymus vulgaris leaf extract-supported approach following the calcination process. 50 mg L−1 MB and 50 mg L−1 SR dyes were completely photodegrade under UV irradiation after only 20 and 45 minutes, respectively, in the presence of 1.0 mg/mL ZnO NPs. When they are exposed to visible light, the degradation efficiency reached 91 and 75% within 60 and 120 min, respectively. Photocatalytic measurements of RTW depict that 95% (within 60 min under UV illumination) and 79% (within 90 min under visible illumination) were degraded, respectively. The enhanced photodegradation can be attributed to the narrowing of the bandgap of the ZnO NPs, high crystallinity and nearly hexagonal morphology with an average size of 20–30 nm. The present results show that ZnO NPs could potentially be applied for high-efficiency degradation of organic dyes and RTW under both UV and visible light irradiation. We report for the first time, Thymus vulgaris leaf extract–assisted synthesis of ZnO nanoparticles (NPs) has been applied as a photocatalytic dye and RTW degradation. Second, our synthesis approach is more facile and simple than the previous method where complex hydrothermal or solvothermal methods have been applied, which leads to a complex preparation procedure. We systematically prepared ZnO materials in taking account into the variable Thymus vulgaris/ZnO precursor ratio, different calcination temperature and time and in detail, their photocatalytic activity has been fully investigated. [ABSTRACT FROM AUTHOR]

In the past decades, great efforts have been made to develop novel visible‐light photocatalysts to achieve high photocatalytic efficiency by utilizing visible light, the largest proportion of solar energy. As a new type of photocatalyst materials, all‐inorganic lead‐free halide double perovskites have begun to attract widespread interest. Herein, double perovskite Cs2AgBiCl6 was developed into a visible‐light photocatalyst for degrading organic dyes. Cs2AgBiCl6 was prepared by the hydrochloric acid precipitation and anti‐solvent recrystallization methods, respectively, and was used to degrade organic dyes under visible light. Samples prepared by the anti‐solvent recrystallization method are smaller than those prepared by the hydrochloric acid precipitation method, which can degrade 95.7 % of Sudan III in 10 min and show excellent photocatalytic activity. The cyclic experiments demonstrate that Cs2AgBiCl6 has a good cycle stability. Moreover, Cs2AgBiCl6‐AS also exhibits good photocatalytic degradation ability for Methyl red and Malachite green. These distinctive results indicate that Cs2AgBiCl6 may be a promising material for developing novel, high‐efficient and stable visible‐light photocatalysts. [ABSTRACT FROM AUTHOR]

In this work, α-MnO 2 /BiVO 4 nanocomposites with varying MnO 2 contents (0–7 wt%) were successfully prepared via the simple chemical method. The structure, morphology, and optical properties of prepared nanocomposites were studied by various analytical techniques including X-ray diffraction (XRD), scanning electron microscopy (SEM), UV–visible absorption spectroscopy, and photoluminescence (PL) spectroscopy. The photocatalytic efficiency of α-MnO 2 /BiVO 4 nanocomposites was studied via decomposition of rhodamine B (RhB) and tetracycline (TC) under exposure to visible light (λ ≥ 420 nm). Due to good structure and composite advantages, 5%MnO 2 /BiVO 4 (MnBV-5) photocatalyst exhibited superior RhB and TC degradation efficiency to all other samples. In addition, the MnBV-5 photocatalyst showed good stability, and no apparent reduction in photocatalysis efficiency was noted after five testing cycles. Therefore, the MnO 2 /BiVO 4 nanocomposite demonstrated a good potential for photocatalytic decomposition of new water contaminants. [ABSTRACT FROM AUTHOR]

Designing of an effectual heterostructure photocatalyst for catalytic organic pollutant exclusion has been the subject of rigorous research intended to resolve the related environmental aggravation. Fabricating p-n junctions is an effective strategy to promote electron-hole separation of semiconductor photocatalysts as well as enhance the organic toxin degradation performance. In this study, a series of n-type NiAlFe-layered triple hydroxide (LTH) loaded with various ratios of p-type MoS 2 was synthesized for forming a heterostructure LTH/MoS 2 (LMs) by an in situ hydrothermal strategy. The photocatalysts were characterized by XRD, SEM&EDX, TEM, FT-IR, XPS, as well as UV–vis DRS. The photoactivity of photocatalysts was tested by the degradation of Indigo Carmine (IC) dye. The optimized catalyst (LM1) degrades 100% of indigo dye in high alkaline pH under UV light for 100 min. Besides, the degradation rate of LM1 is 15 times higher than that of pristine NiAlFe-LTH. The enhanced photoactivity is attributed to the synergistic effect between NiAlFe-LTH and MoS 2 as well as the p-n junction formation. [Display omitted] • A facile method for synthesizing heterostructure-LMs photocatalyst is suggested. • The best photocatalytic performance was found in LM1 samples for dye degradation. • Superior adsorptive-photocatalytic activity of LM1 was revealed under visible light. • Photocatalytic performance of LMs was effectively exhibited even at high pH over 11. • The recyclability and mechanism of photocatalysis of LMs was identified. [ABSTRACT FROM AUTHOR]

Wastewater containing organic dyes is harmful to the ecological environment and human health. Graphitic carbon nitride (g-C 3 N 5) is suitable for the photocatalytic degradation of organic dyes, but its photocatalytic activity is low due to several drawbacks. A series of Ag–CeO 2 /g-C 3 N 5 composites with different morphologies of Ag–CeO 2 have been prepared in order to improve the photocatalytic activity of g-C 3 N 5. The photocatalytic activities of the Ag–CeO 2 /g-C 3 N 5 composites were investigated using rhodamine B (RhB) as the target pollutant. When compared with Ag–CeO 2 spheres and g-C 3 N 5 , the charge separation efficiency and photocatalytic activity of the Ag–CeO 2 /g-C 3 N 5 heterostructure were significantly improved. The photodegradation rate of RhB using 50 wt% Ag (1.50)-CeO 2 (sphere)/g-C 3 N 5 was 96.5 %, while pure g-C 3 N 5 and Ag (1.50)-CeO 2 spheres was 30.8 and 9.9 %, respectively. This was attributed to the synergistic effect of the heterojunction comprised of Ag, CeO 2 , and g-C 3 N 5. As an electronic medium, Ag transfers electrons between g-C 3 N 5 and CeO 2 , which can promote electron-hole separation and improve the photocatalytic activity. The 50 wt% Ag (1.50)-CeO 2 (sphere)/g-C 3 N 5 composites also had fair photocatalytic stability and · O 2 − plays a dominant role in the RhB photodegradation process. In addition, the photocatalytic mechanism of 50 wt% Ag (1.50)-CeO 2 (sphere)/g-C 3 N 5 has also been described. [Display omitted] • Series Ag–CeO 2 /g-C 3 N 5 composites were synthesized with respective morphologies of Ag–CeO 2. • Loading Ag–CeO 2 on g-C 3 N 5 can improve the specific surface area and photocatalytic property. • The photodegradation to RhB of 50 wt% Ag–CeO 2 /g-C 3 N 5 composites can reach 96.5 % within 150 min. • The 50 wt% Ag–CeO 2 /g-C 3 N 5 composites have good photocatalytic activity and chemical stability. [ABSTRACT FROM AUTHOR]

In pursuit of the appropriate method for complete removal of organic effluents from surface water, Ag modified g-C 3 N 4 materials as a photocatalyst gained considerable attention. In this paper, Ag doped g-C 3 N 4 materials were prepared by a facile one-pot pyrolysis method. The synthesized photocatalysts were studied using different analytical techniques like XRD, HR-TEM, XPS, UV, FTIR, PL spectroscopy, etc. The prepared photocatalyst materials were used for the visible light photodegradation of IC dye as an organic pollutant and for self-cleaning applications. The obtained results indicate that the optimized Ag doped g-C 3 N 4 (CNA-1) sample exhibits 79.97 % degradation efficiency in 30 min with efficient self-cleaning performance. The enhanced photocatalytic activity of CNA-1 can be attributed to the incorporation of Ag, which plays a pivotal role in absorbing visible light. Furthermore, cycling tests were employed to evaluate the stability and reusability of material. The possible photocatalytic mechanism was proposed from trapping experiments. [Display omitted] [ABSTRACT FROM AUTHOR]

The layered Bi3O4Br nanoplates were synthesized through a simple calcination process, which can simultaneously harvest visible light and ultrasonic vibration to realize the effective piezo-photocatalysis. The piezo-photocatalysis over the Bi3O4Br leads to a great enhancement in catalytic efficiency with respect to the pure photocatalysis or piezocatalysis. The apparent rate constant of piezo-photocatalysis for the degradation of MO achieves to be 0.008 min − 1 , which is 5.20 and 1.51 times as high as the individual piezocatalysis and photocatalysis, respectively. This enhancement would be attributed to the built-in piezoelectric field induced by ultrasonic vibration facilitating the separation of charge carriers in photoexcited Bi3O4Br. [ABSTRACT FROM AUTHOR]

[Display omitted] • Flower-like Cu-doped In 2 S 3 was constructed through a one-step hydrothermal method. • Cu-doping enhanced visible-light response and BET surface area of In 2 S 3. • Cu-doped In 2 S 3 exhibited excellent adsorption and catalytic degradation activity of Rhodamine B. • Superoxide ion radical was the main active substance in initiating the degradation of Rhodamine B. In 2 S 3 materials doped with different concentrations of copper ions (Cu-In 2 S 3) were designed and synthesized, which successfully improves the response to visible light, separation of carriers, and adsorption for rhodamine B of In 2 S 3. Cu-doping improves the photocatalytic activity of In 2 S 3 for dye removal. In 2 S 3 doped with 0.3% Cu2+ exhibits the highest photocatalytic activity for the degradation of rhodamine B. In addition, it shows high photocatalytic stability. The photocatalytic active species capture experiments show that the superoxide radical was the main active substance for the photocatalytic degradation of rhodamine B over 0.3% Cu-In 2 S 3. This study provides a valuable reference for the construction of In 2 S 3 -based photocatalytic materials. [ABSTRACT FROM AUTHOR]

• Prepared composite nanofiber membrane possesses a good photocatalyst performance. • High degradation activity of organic dyes under visible light. • The composite nanofibers membrane possessed excellent recovery and reuse. • The free-standing membrane is flexible and easy to handle. • The flexibility of the composite nanofibers allows use in a continuous operation. This study proposed an effective method by using photocatalytic composite nanofiber membranes in order to degrade malachite green (MG) and acid red 27 (AR 27) to harmless products. The photocatalytic composite nanofiber membrane, Polyacrylonitrile (PAN) was incorporated with catalyst SiO 2 and TiO 2 photocatalyst. The PAN/SiO 2 -TiO 2 -NH 2 nanofiber membrane was synthesized by electrospinning technique followed by chemical crosslinking. The results of SEM, EDX, FTIR and XRD confirmed the successful preparation of nanofiber membrane. XRD analysis shows the confirmation of SiO 2 and TiO 2 peaks. The result shows that PAN/SiO 2 -TiO 2 -NH 2 nanofiber membrane exhibit the highest degradation with a good distribution of SiO 2 and TiO 2 on the PAN nanofiber membrane surface. The results showed that the complete photodegradation of MG and AR 27 with artificial visible-light was achieved after 9 and 25 min, respectively. In addition, the nanofiber membrane exhibited good stability and reusability for MG and AR 27 photodegradation and has potential to be applied in industrial application. [ABSTRACT FROM AUTHOR]

• A 2D covalent organic framework Por-PD-COF as selective adsorbent and photocatalyst was designed and synthesized. • Por-PD-COF could selectively and competitively adsorb MB from the mixed organic dyes aqueous solution. • Por-PD-COF could photodegrade MB effectively under visible light. • Por-PD-COF can be recycled and reused after absorption or photocatalysis. In this work, amide bonds linked 2D porphyrin-based covalent organic framework (Por-PD-COF) was designed and synthesized through condensation reaction between meso -tetrakis (p -carboxyphenyl) porphyrin (TCPP) and para -phenylenediamine (PD). Large surface area, abundant active sites and good stability of Por-PD-COF made it can quickly and efficiently absorb methylene blue (MB) selectively and remove it from aqueous solution. More importantly, in different mixture of organic dyes including RhB and MB, MB and MO, Por-PD-COF can selectively adsorb MB with a large adsorption capacity (328.57 mg·g−1), while a little MO and hardly RhB because of the unique charge selectivity and specific pore size. Especially in the mixture solution of MO and MB, compatitive adsorption appeared, MB can substitute the adsorbed MO on the active sites in the channel of Por-PD-COF. Furthermore, with the band gap narrow to 1.02 eV, Por-PD-COF could be used as efficient photocatalyst to degrade MB (99%, 180 min) directly under visible light irradiation, and can be reused for four times with almost no absorptive and photocatalytic capacity losing. The possible adsorption and photocatalytic mechanisms of Por-PD-COF were also proposed. As a result, with the uncomplicated preparation, effective and selective adsorption and reusability, Por-PD-COF was a promising specific adsorbent and photocatalyst for further application in specific organic molecules separation and organic waste removal from aqueous solution. [ABSTRACT FROM AUTHOR]

Abstract Here we propose new type II semiconducting nanocomposite TiO 2 /CoSe for effective separation of the photo-induced charges, thus enhancing the visible light harvesting capability of TiO 2. The formation of TiO 2 /CoSe nanocomposite is confirmed by XRD, FE-SEM, HR-TEM, XPS and BET characterization techniques. Remarkable results were obtained during photodegradation study of both Rhodamine B (99.86%) and methylene blue (97.85%) within just 90 min of visible light irradiation. The mechanistic investigation demonstrates that the Superoxide (O 2 −) radicals are most reactive species participates in photocatalytic dye degradation. The synthesized photocatalyst has good reusability, it can be successfully reused for six batches of photocatalytic reactions. Graphical abstract Unlabelled Image Highlights • Rutile TiO 2 nanorods decorated with CoSe nanoparticles. • TiO 2 /CoSe nanocomposite: a visible light harvesting type II semiconductor • Enhanced photocatalytic efficiency is attributed to the retarded rate of recombination of photoexcitons. • Superoxide radical is most reactive species responsible for the photodegradation. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Vanadium oxide improved the photocatalytic activity of four different supports. • Brønsted acid sites concentration on V 2 O 5 /ZM5 and V 2 O 5 /TiO 2 is higher than V 2 O 5 /SBA. • Remarkable photocatalytic activity was observed on V 2 O 5 /ZM5 under visible light. • V4+ species and Brønsted acid sites improved the photocatalytic degradation of Eosin Y. • V 2 O 5 supported on TiO 2 and zeolite ZM5 are highly efficient to eliminate organic dye pollutants. Abstract SBA, zeolite-ZM5, TiO 2 and P25, used as dispersant agents of vanadium oxide, were synthesized. The supports (SBA, Zeolite-ZM5, TiO 2 and P25) were loaded with 3 wt.% of V 2 O 5. V 2 O 5 /ZM5, V 2 O 5 /P25 and V 2 O 5 /TiO 2 showed high photocatalytic activity for the degradation of Eosin Y employing a visible light source (450 nm). The photocatalysts were characterized by X-ray diffraction, XPS, UV-vis, S BET , SEM, TEM, and FTIR (surface acidity). Under visible light, the photocatalytic degradation rate displayed the following order V 2 O 5 /TiO 2 (93%) > V 2 O 5 /P25 (81%) > V 2 O 5 /ZM5 (70%) > V 2 O 5 /SBA (55%). This behavior is in conjunction attributable to the oxidation state of the vanadium species V4+ and the presence of Brønsted acid sites. The structure and properties of the TiO 2 play an important role during the photodegradation of the Eosin Y. Results here obtained give new insights for the water treatment processes using visible light over vanadium photocatalysts. [ABSTRACT FROM AUTHOR]

Abstract Photocatalysis, a green technique is widely applied in the fields of environmental remediation for the removal of many pollutant constituents. It is known that major problems related to the present photocatalytic system, which significantly limit their photocatalysis efficiency, are low-usage of visible light, fast recombination and also the low migration ability of the photo-generated electrons and holes. To solve the problem associated with conventional photocatalytic systems, recently hybrid photocatalysts containing carbon quantum dots (CQDs) have been proposed. The tunable photocatalytic characteristics of CQDs are widely mentioned. Moreover, the excellent photocatalytic activity of CQDs alone and in combination with photoactive species in the photo-degradation of organic pollutants was confirmed in the many reports. This work presents a comprehensive view of the application of CQDs to improve conventional photocatalytic systems in those studies which considered organic dyes as sample pollutants. In addition to providing detailed information regarding important roles of CQDs in photocatalytic activity enhancement, this review provides the comprehensive details about findings of the photocatalytic degradation of dyes using CQD-based photocatalysts and the best CQD-based composites photocatalysts are highlighted. Highlights • Combination of CQDs/conventional photo-catalysis systems improved their performance. • Multifunctional roles of CQD in photo-catalysis ate extensively elucidated. • CQD-based photo-catalysis degradation of organic dyes is comprehensively reviewed. [ABSTRACT FROM AUTHOR]

Heterojunction with nano-level interfacial contact has an advantage in improving the transfer capacity of photongenerated carriers. In consequence, a heterojunction composite with nano-level interfacial contact was developed by establishing CdSe/Al 2 TiO 5 heterojunction composites. The heterojunction composite was established by combining Al 2 TiO 5 and CdSe nanocrystals. They provided superior nano-level interfacial contact. The photocatalytic activity of heterojunction composites were illustrated to be significantly improved compared to that of pure Al 2 TiO 5 and CdSe nanocrystals. Moreover, the photocurrent intensity of heterojunction composites displays a several times enhancement, implying the promotion of photocatalytic activity was owned to the nano-level interfacial contact with ideal photogenerated electron-hole pairs transfer behavior. [ABSTRACT FROM AUTHOR]

[Display omitted] • Ag 6 Mo 10 O 33 /g-C 3 N 4 1D-2D heterojunction was prepared via chemical deposition. • Ag 6 Mo 10 O 33 /g-C 3 N 4 consists of Ag 6 Mo 10 O 33 nanowires and g-C 3 N 4 nanosheets. • It is highly efficient for degradation of organic dyes under visible light. • Superoxide radical anions and photogenerated holes are main active species. The construction of heterojunctions is an effective way to improve the activity of photocatalysts. Most heterojunction photocatalysts are portrayed by the deposition of semiconductor nanoparticles on other semiconductor supports (often 3D particles or 2D sheets), but 1D-2D hybridized heterojunctions portrayed by the supporting of semiconductor nanowires onto semiconductor nanosheets are rare. Herein, we report a novel Ag 6 Mo 10 O 33 /g-C 3 N 4 1D-2D hybridized heterojunction with highly enhanced visible-light-driven photocatalytic activity. Ag 6 Mo 10 O 33 nanowires were in situ loaded onto g-C 3 N 4 nanosheets by controlling the pH value (∼2) of the synthesis mixture. The resulting Ag 6 Mo 10 O 33 /g-C 3 N 4 heterojunction was found to be much more active than pristine Ag 6 Mo 10 O 33 , g-C 3 N 4 , or a mechanical mixture of both in the photocatalytic degradation of methyl orange (MO), Rhodamine B (RhB), and methylene blue (MB) under visible light irradiation. Through relevant characterization, the high activity of Ag 6 Mo 10 O 33 /g-C 3 N 4 heterojunction was mainly attributed to the efficient separation of photogenerated charge carries. Superoxide radical anions (O 2 −) and photogenerated holes (h+) were found to be the main active species. [ABSTRACT FROM AUTHOR]

Photocatalysis can be a potential technique for decomposing antibiotics contaminants from water. In this study, g-C 3 N 4 modified Bi/BiOBr nanosphere were prepared by a simple microwave solvothermal method, and the structure-properties relationships of the Z-scheme heterojunction were evaluated in degrading organic dyes. Various characterization techniques were then applied to elucidate the structure-performance relationships of the resulting heterojunction photocatalysts in degrading CIP. Compared with pristine g-C 3 N 4 or Bi/BiOBr, the g-C 3 N 4 @Bi/BiOBr nanocomposites showed heightened property in photocatalytic degradation of CIP. The photocatalytic efficiency of CIP decomposition over the Z-scheme of g-C 3 N 4 @Bi/BiOBr heterojunction was about 2.38 and 1.35 times homologous to those of original g-C 3 N 4 and Bi/BiOBr. The enhancement in photocatalytic activity of g-C 3 N 4 @Bi/BiOBr could be described by the Z-scheme pathway and the SPR effect of Bi0, which broadened visible light absorption and promoted the separation of photoinduced carriers. In addition, the effect of typical water matrix factors, such as pH, anionic, and cationic on photodegradation rate were evaluated. Furthermore, results of scavenging experiments showed that ·OH, ·O 2 −, and h+ all participate in the degradation of CIP. Based on the band structure and scavenging measurements, a possible photocatalytic mechanism for the as-synthesized g-C 3 N 4 @Bi/BiOBr composites was proposed. • Prepared g-C 3 N 4 @Bi/BiOBr composites by one-step microwave solvothermal method. • The introduction of g-C 3 N 4 effectively improved the separation of photogenerated carriers. • The high concentration of H+ inhibits the formation of ·O 2 −. Zn2+ and CO 3 2− inhibit the photocatalytic process most. • The ternary composites showed good practicability under sunlight. A reasonable photocatalytic mechanism was proposed. [ABSTRACT FROM AUTHOR]

[Display omitted] • MOF materials such as NH 2 -UiO-66 was decorated for the first time with FeOOH QDs. • The prepared NH 2 -UiO-66/FeOOH QDs photocatalyst was used for water remediation. • Photo-Fenton activity of photocatalyst was found greater than individual MOF and QDs. • Transfer of photo-excited e- from MOF to FeOOH QDs resulted to charge separation. • Both h+ and •OH were responsible for efficient degradation of pollutants. Coupling of inexpensive and easily synthesized FeOOH quantum dots (QDs) with metal–organic frameworks (MOFs) is an outstanding subject in photocatalysis field, which no research works have been reported in this regard so far. For this purpose, a novel photocatalyst was prepared by in-situ formation of different amounts of FeOOH QDs (5, 10 and 15 wt%) in the presence of NH 2 -UiO-66 as visible light-harvesting MOF. HR-TEM analysis revealed uniform decoration of NH 2 -UiO-66 with 2–5 nm sized FeOOH QDs. Photo-Fenton behavior of the resulted NH 2 -UiO-66/FeOOH(10 %) composite in the degradation of methyl violet (MV) was found to be higher than other composites with different loadings of FeOOH QDs. The effect of H 2 O 2 and photocatalyst dosage were also investigated and the best degradation efficiency of 82.2 % was achieved at optimal reaction conditions. It was observed that both FeOOH QDs and NH 2 -UiO-66 demonstrated poor photocatalytic activity individually, but their composite resulted in outstanding photo-Fenton activity because of effective electron transfer from photo-excited NH 2 -UiO-66 to FeOOH QDs. Scavenging experiments indicated that hydroxyl radicals and photo-generated hole are the main species responsible for photo-Fenton degradation of water contaminants. [ABSTRACT FROM AUTHOR]

Photocatalysis is one of the effective methods to alleviate the urgent pressure on energy shortage and environmental pollution in modern world, for which TiO 2 has attracted great attention due to its excellent photocatalytic activity, high stability, non-toxicity and low cost. However, the wide band gap (about 3.2 eV), easy recombination between photogenerated electrons and holes, as well as easy agglomeration and difficult recycling of traditional nanomaterials limit its wide application. Herein, novel (N,F)-co-doped TiO 2-δ nanofibers were successfully prepared simply by thermally treating electrospun nanofibers under Ar atmosphere using polyacrylonitrile as the reductive agent, tetrabutyl titanate as the titanium source and trifluoroacetic acid as the fluorine source. The resultant product can be directly used as photocatalysts for degrading environmental pollutants, which can remove 27.2% of rhodamine B, 40.9% of methylene blue and 31% of Cr(VI) within 60 min under visible light irradiation from a 5 W LED lamp, being almost 11.8, 3.2 and 2.8 times those over its commercially available TiO 2 counterpart, respectively. The present work will provide a simple strategy to feasibly prepare various high-performance photocatalysts. [Display omitted] • Novel (N,F)-co-doped TiO 2-δ nanofibers. • Facile and highly efficient synthesis method based on electrospinning. • High efficient solar-driven photocatalysts for environmental remediation. • Mechanism for improved photocatalytic activity. [ABSTRACT FROM AUTHOR]

Highlights: [•] Styrene–tin (IV) phosphate nanocomposite (ST/TPNC) ion exchanger was chemically prepared by simple sol–gel method at pH 0–1. [•] ST/TPNC exhibited higher ion exchange capacity as compared to its inorganic component. [•] ST/TPNC retained about 35.5% of the initial value of ion exchange capacity after heating up to 400°C. [•] ST/TPNC was used as efficient photocatalyst for the degradation of MB dye from aqueous system in the presence of solar light. [•] The pH titrations studies confirmed the monofunctional strong cationic nature of ST/TPNC. [ABSTRACT FROM AUTHOR]

[Display omitted] • The CNTC hybrids exhibited excellent photocatalytic activity. • The Ti 3 C 2 loading improved the charge mobility and catalytic sites of g-C 3 N 4. • Enhanced activity mechanism and roles of active species were elucidated. The g-C 3 N 4 has received extensive attention for its unique properties. However, g-C 3 N 4 still suffers from the intrinsic limitations, which limit its large-scale applications. Hence, it is an urgent requirement to find a high-performance g-C 3 N 4 photocatalyst possesses both a high separation rate of charge carriers and a strong light response. In this work, we have designed a 3D/2D g-C 3 N 4 /Ti 3 C 2 (CNTC) heterojunction with a 3D interconnected porous structure as high efficiency photocatalyst for the photocatalytic hydrogen evolution (Pt as co-catalyst) and contaminant degradation. Benefiting from the 3D interconnected morphology and the incorporation of Ti 3 C 2 nanosheets, the CNTC hybrids exhibit a high specific surface area (85.08 m2 g−1) and highly efficient charge migration, thus leading to excellent catalytic performance for the hydrogen generation and organic dye elimination. In addition, the mechanism of improved photocatalytic performance was analysed by characterization measurements, active species analysis and density functional theory calculations. [ABSTRACT FROM AUTHOR]

• MnS/Ag 2 WO 4 NCs was prepared by chemical co-precipitation method. • The NCs showed efficient visible light photocatalytic activity than individual particles. • MnS/Ag 2 WO 4 showed potent anti-microbial activity against gram positive and gram negative microorganisms. • Experimental results demonstrated that OH• and •O2- are the major reactive species involved in dye degradation. • MnS/Ag 2 WO 4 NCs showed MB dye degradation potency of 92.3%. In this study, the novel MnS/Ag 2 WO 4 photocatalyst was synthesized via chemical co-precipitation method and investigated its physical and structural characteristics using HR-TEM, N 2 adsorption and desorption studies, FT-IR, EDAX, PL, UV–vis DRS, ESR, XPS and XRD. The estimation of photocatalytic activity of synthesized photocatalysts was done using methylene blue (organic dye) in aqueous solution. The photocatalyst efficiency was superior for MnS/Ag 2 WO 4 with degradation of 92.3% when compared with bare MnS (67.23%) and Ag 2 WO 4 (58.93%). The kinetic study reveals that higher reaction kinetic rate achieved by the MnS/Ag 2 WO 4 compared with MnS and Ag 2 WO 4. The scavenging test reveals that •OH and O2-• took the important part in the degradation process. The six cycles test reveals that the photocatalyst is highly reusable by showing similar degradation efficiency throughout the six cycles. MnS/Ag 2 WO 4 was also possessed potential broad spectrum anti-microbial activity against B. subtilis and E. coli. Hence, MnS/Ag 2 WO 4 heterostructure can be used as an excellent photocatalyst as well as an effective anti-microbial agent. MnS/Ag 2 WO 4 would be a cost-effective, highly efficient photocatalyst and a good antimicrobial agent. [ABSTRACT FROM AUTHOR]

[Display omitted] • Facile green ultrasonic-assisted synthesis of novel Ag@RGO/g-C 3 N 4 nanocomposites. • Ag and RGO significantly decrease the bandgap energy of g-C 3 N 4 from 2.65 to 1.97 eV. • Ag and RGO achieved a superior reduction in the e–h recombination rates of g-C 3 N 4. • Ag and RGO caused a synergetic enhancement in the photocatalytic activity of g-C 3 N 4. • Ag@RGO/g-C 3 N 4 exhibited higher adsorption capability compared to bare g-C 3 N 4. Visible-light-driven photocatalysis can be considered as an eco-friendly approach for the effective treatment of wastewater, where 2D g-C 3 N 4 -based photocatalysts exhibited outstanding performance in this approach. Thus, a green simple one-pot ultrasonic method was utilized for the first time, with in-situ reduction of Ag+ and GO, to synthesize an innovative ternary nanocomposite of g-C 3 N 4 nanosheets, Ag quantum dots, and RGO nanosheets. The samples were analyzed by several techniques including PXRD, FE-SEM, HR-TEM, XPS, DRS, and PL. The anchoring of RGO nanosheets and Ag quantum dots on the surface of g-C 3 N 4 nanosheets caused an outstanding improvement of its visible light absorption, a remarkable reduction of its bandgap energy from 2.65 to 1.97 eV, an unprecedented decline in the e–h recombination rate, a complete removal of Rhodamine-B dye through adsorption, and a unique improvement in the photodegradation of Amaranth dye. Finally, the mechanism of the synergetic improved photocatalytic behavior of Ag@RGO/g-C 3 N 4 nanocomposites was suggested. [ABSTRACT FROM AUTHOR]

• In situ synthesis of Bi 2 S 3 /BiVO 4 /TiO 2 ternary heterostructured arrays. • The Bi 2 S 3 /BiVO 4 /TiO 2 photocatalyst with superior visible light absorption. • Excellent photoelectrochemical and photocatalytic properties of Bi 2 S 3 /BiVO 4 /TiO 2 photocatalysts. • The Bi 2 S 3 /BiVO 4 /TiO 2 ternary heterostructure with a unique double Z-scheme charge transfer mechanism. In this study, novel double-Z-scheme Bi 2 S 3 /BiVO 4 /TiO 2 (BVT) heterostructured photocatalysts were prepared using continuous hydrothermal methods. The in situ conversion of BiVO 4 /TiO 2 (VT) binary photocatalysts into BVT ternary photocatalysts with large optical absorption coefficients was achieved. Compared to TiO 2 nanorod (TNR) arrays, BVT photocatalysts extend the light absorption range to the near-infrared with consistently high absorption intensities. Photoelectrochemical tests demonstrate that BVT(4) achieves the highest transient photocurrent (110 µA/cm2) of approximately 11 times that of TiO 2 (10 µA/cm2). The photocatalytic performances of all samples were investigated by degrading methyl orange (MO) under visible light irradiation. The results show that BVT(4) possesses the best degradation efficiency (76.3%) which is about 4 times higher than that of bare TNR (19.7%). The outstanding photocatalytic performance can be attributed to the double Z-scheme charge transfer path, which effectively promotes the separation and transfer of electron-hole pairs, resulting in a strong redox activity of the accumulated charge to decompose organic dyes during a degradation reaction. [ABSTRACT FROM AUTHOR]

In this work, SnO 2 nanoparticles (NPs) were grown in-situ on g-C 3 N 4 nanosheets using a microwave-assisted hydrothermal method. The resulting nanocomposite formed heterojunctions with useful photocatalytic properties. The morphology and chemical structure of the g-C 3 N 4 /SnO 2 were thoroughly characterized. UV–vis and photoluminescence results revealed g-C 3 N 4 /SnO 2 heterojunction with strong light adsorption and enhanced efficient separation of electron-hole pairs, respectively. These properties provided an excellent photocatalytic efficiency of the g-C 3 N 4 /SnO 2 catalysts towards Rhodamine B degradation under UV and visible light irradiation, which were 100% and 98.5%, respectively, after 4 h of exposure to light. Such efficient materials could be used for future degradation of organic dyes under solar light. In addition, these composite materials could be applied to environmentally friendly photocatalysis reaction. [ABSTRACT FROM AUTHOR]

The present investigation reports on research of pure molybdenum disulfide (MoS 2) and MoS 2 doped CoO@meso-CN nanohybrids with various concentration. The photocatalytic action of MoS 2 doped CoO@meso-CN nanohybrids was established by photodegrading methylene red (MR), methylene orange (MO) and congo red (CR) under visible light irradiation. The efficient visible light driven photocatalytic action was owing to a larger specific surface area of MoS 2 , which enhanced the close interfacial contact between pollutants and photocatalysts. Thus, when employed as photocatalyst for organic pollutants photodegradation, the developed nanohybrid exhibits a degradation rate of 0.072 min−1, which is high increasing compared with that of pure CoO/meso-CN and MoS 2 (0.014 min−1 and 0.032 min−1). In addition, the nanohybrids indicates excellent stability and remarkable organic dyes removal capability, which could provide as a potential photocatalyst for water remediation under visible light. The resultant MoS 2 doped CoO@meso-CN nanohybrids exhibit excellent photocatalytic capacity for MR, MO and CR (average removal rate was 94% at pH values of 3) within 60 min. The following demonstrated that synthesized MoS 2 doped 1 wt% CoO@meso-CN nanohybrids retained a great photocatalytic as compared to pure MoS 2 and CoO/meso-CN photocatalysts for degradation of organic dyes. The cases were described using XRD, FESEM, FTIR, HRTEM, XPS, TGA, UV–vis, Raman and EPR spectroscopy analyses. Our results serve a pathway for the fabrication of a MoS 2 -based heterostructure nanohybrids which can be applied for environmental management and reusability regions. Image 1 • A simple method for the preparation of molybdenum disulfide heterostructure is described. • Synergistic effect of heterostructure nanohybrids is improves the photodegradation efficiency. • Heterostructure nanohybrids are used for organic pollutants (methylene red, methylene orange and Congo red) degradation. • Nanohybrid exhibited excellent reusability property up to five cycles. [ABSTRACT FROM AUTHOR]

Photocatalysis is one of the most promising techniques for degrading organic dyes under ambient conditions, due to that it has the characteristics of green and environmentally friendly. However, inhibited by the rapid recombination of the photogenerated charges and the low utilization of visible light, this process requires efficient photocatalysts to solve those problems. Herein, we report our recently finding that the MIL-53(Fe)/Bi 2 WO 6 heterostructure as a high-efficient photocatalyst for Rhodamine B (RhB) and phenol degradation with excellent performance and photocatalytic stability. The catalytic rate constant of MIL-53(Fe)/Bi 2 WO 6 (5 wt% MIL-53(Fe) for RhB and phenol degradation are 3.75 and 3.27 times higher than that of pur Bi 2 WO 6 , respectively. By introducing MIL-53(Fe) into Bi 2 WO 6 , the specific surface area becomes larger exposing more active sites and the band-gap width becomes narrower, which increases transfer rate of photogenerated electrons to the surface enhancing the electron-hole separation. Moreover, it also increased the absorption of visible light and improved the photocatalytic activity, which forcefully demonstrate that MIL-53(Fe)/Bi 2 WO 6 is a promising photocatalyst for the removal of organic pollutants. Finally, the possible mechanism of photocatalytic degradation was discussed. MIL-53(Fe)/Bi 2 WO 6 as an effective photocatalyst for Rhodamine B degradation. When tested in 20 mg L−1 RhB solution, the degradation rate can up to ~98% after 80 min under visible light irradiation. Meanwhile, this photocatalyst shows outstanding stability and durability. Image 1 • MIL-53(Fe)/Bi 2 WO 6 used as an efficient photocatalyst for Rhodamine B and phenol degradation. • MIL-53(Fe)/Bi 2 WO 6 shows high stability and durably. • MIL-53(Fe)/Bi 2 WO 6 endowed the superior transfer and separation of photogenerated carriers. • Such photocatalyst gets remarkable performance for Rhodamine B and phenol degradation. [ABSTRACT FROM AUTHOR]

A series of novel Fe(III) clusters modified Bi 12 O 17 Cl 2 (Fe/Bi 12 O 17 Cl 2) photocatalysts have successfully fabricated. Their chemical structure, element composition, surface feature, light response ability and photocatalytic activity were measured. The results revealed that Fe(III) clusters uniformly loaded on Bi 12 O 17 Cl 2 nanosheets surface, which resulted Fe/Bi 12 O 17 Cl 2 possessing improved visible light harvesting efficiency and introduced interfacial charge transfer effect in Fe/Bi 12 O 17 Cl 2 photocatalyst, conducing to photoinduced charge efficiently separation. Its photocatalytic ability was performed by degrading organic dye (Rhodamine b). Comparing with the degradation rate of Bi 12 O 17 Cl 2 (0.0743 min−1), that of Fe/Bi 12 O 17 Cl 2 photocatalyst was obviously enhanced (0.157 min−1). Clearly, Fe/Bi 12 O 17 Cl 2 photocatalyst had the improvement of photoproperty. Then, the results of trapping experiments revealed the key active species were O 2 − and h+. Lastly, a reasonable photocatalytic mechanism over Fe/Bi 12 O 17 Cl 2 photocatalyst was shown. [ABSTRACT FROM AUTHOR]

This paper reports the facile synthesis of cubic-shape hematite (α-Fe 2 O 3) which was directly anchored with gold nanoparticles (GNPs), so-called cubic Fe 2 O 3 @GNPs. The cubic Fe 2 O 3 @GNPs exhibited enhanced photocatalytic activity under visible light. Furthermore, the cubic Fe 2 O 3 @GNPs exhibited higher photocatalytic activity to the cationic dye than the anionic dye, probably due to the adsorption-assisted photocatalytic degradation. • Hydrothermal synthesis of cubic hematite (cubic Fe 2 O 3). • Au seeds were directly anchored on the cubic Fe 2 O 3 with amine groups. • Au seeds were grown into gold nanoparticles (GNPs), forming cubic Fe 2 O 3 @GNPs. • Higher photocatalytic activity of cubic Fe 2 O 3 @GNPs to the cationic dye. This paper reports the facile synthesis of amine-functionalized cubic hematite (Fe 2 O 3) via hydrothermal reaction between Fe3+ and diamine ligand. The cubic Fe 2 O 3 was directly anchored with negative Au seeds (<10 nm), which were grown into large gold nanoparticles (GNPs) using an ascorbic reducing agent. The resulting cubic Fe 2 O 3 @GNPs exhibited enhanced photocatalytic activity in the degradation of methylene blue (MB) and methyl orange (MO) dyes under visible light. The photocatalytic activity of cubic Fe 2 O 3 @GNPs was optimized by adjusting the size of GNPs and inter-particle distance between them, which were favorable for visible light absorption and separation of electro-hole pairs. Furthermore, the cubic Fe 2 O 3 @GNPs exhibited higher photocatalytic activity to the cationic MB dye than the anionic MO dye, due to its adsorption-assisted photocatalytic degradation of organic dyes. The hydrothermal synthetic route is very effective to prepare metal oxide photocatalyst with surface functionality and unique cubic shape. [ABSTRACT FROM AUTHOR]

The challenges like the removal of organic pollutants from the wastewater, and photocatalytic reduction of N 2 using solar energy are achievable by stable, low cost, and a visible light active semiconductor mediated photocatalysis. A novel 0.4BWO/g-C 3 N 4 heterostructure achieves excellent degradation of cationic/anionic dyes and N 2 reduction under visible light illumination. The 0.4BWO/g-C 3 N 4 exhibits 99.8% degradation efficiency towards the degradation of rhodamine B (RhB), which is 2.2-fold compared to commercial catalyst Degussa P25. 0.4BWO/g-C 3 N 4 composite also efficiently degraded AV7, IC, DB 71 dyes and photo-reduce N 2 to NH 3. The incorporation of BWO nano-octahedron into the g-C 3 N 4 network suppress the recombination of photogenerated electron-hole pairs and follow Z-scheme electron transfer pathway in 0.4BWO/g-C 3 N 4 heterostructure. The notable separation of electron-hole pairs is well described by photoluminescence, time-resolved fluorescence, and impedance spectroscopy study. The finding presented here provides new insight into typical design and engineering of a stable and visible light active heterostructure for degradation of dyes and N 2 reduction. Image 1 • The great advantages of 0.4BWO/g-C 3 N 4 are to neutralize organic dyes and N 2 reduction. • A BWO octahedron nanoparticle makes g-C 3 N 4 for efficient photocatalyst under visible light. • The degradation and N 2 reduction efficiency of the catalyst remain significant after four cycles. • Role of solvent, sacrificial agent, nitrogen atmosphere in N 2 reduction is discussed in brief. • The Z-scheme mechanism involved for degradation and N 2 fixation is elucidated in details. [ABSTRACT FROM AUTHOR]

Ternary Ti 3 C 2 –OH/ln 2 S 3 /CdS composites with an efficient visible-light-driven photocatalytic performance have been prepared via a facile hydrothermal synthesis method. The photo-degradation experiments verified that Ti 3 C 2 –OH/ln 2 S 3 /CdS composite with a large surface area of 68.2 m2/g exhibited an enhanced photocatalytic activity and adsorption capacity towards Rhodamine B under visible light irradiation, which was higher than that of the naked CdS and ln 2 S 3 , respectively. Furthermore, Ti 3 C 2 –OH/ln 2 S 3 /CdS composite showed robust degradation efficiency for mixture dyes of RhB and Methyl Orange (MO), and its catalytic ability was superior to that of ternary GO/ln 2 S 3 /CdS composite. The trapping experiments for active species revealed that hole (h+) and •O 2 − species played a critical role in the removal of organic pollutants. In summary, the enhanced photocatalytic performance of Ti 3 C 2 –OH/ln 2 S 3 /CdS photocatalyst was derived from an excellent charge carrier separation and transfer of Ti 3 C 2 –OH MXene and the synergistic effect between CdS and ln 2 S 3 which resulting in strong visible light response. Image 1 • The Ti 3 C 2 –OH/In 2 S 3 /CdS composite was fabricated via a facile hydrothermal route. • The Ti 3 C 2 –OH/In 2 S 3 /CdS composite exhibited enhanced photo-degradation performance under visible light irradiation. • The photocatalytic mechanism of the Ti 3 C 2 –OH/In 2 S 3 /CdS composite has been investigated carefully. [ABSTRACT FROM AUTHOR]