Photocatalytic Cr Research Articles

Facile fabrication of B-rGO/ZnFe2O4 p-n heterojunction-based S-scheme exciton engineering for photocatalytic Cr(vi) reduction: kinetics, influencing parameters and detailed mechanism.

The fabrication of p-n heterostructures was found to be an effective strategy to stimulate the interfacial exciton shipment and photocatalytic reactions. Herein, we report a p-n junction synthesized by combining p-type boron-doped reduced graphene oxide (B-rGO) with an n-type ZnFe2O4 semiconducting material for Cr(vi) reduction under LED light irradiation. The band structures of ZnFe2O4 and B-rGO were evaluated using UV-vis spectroscopy, Mott-Schottky (M-S) plots and photocurrent studies. The results indicated that ZnFe2O4 and B-rGO exhibit a conventional type-II charge transfer, and the Fermi-level (E F) of ZnFe2O4 was found to be much lower than that of the B-rGO material. Based on these investigations, an S-scheme charge-migration pathway was suggested and demonstrated by the photocatalytic activity and nitroblue tetrazolium (NBT) chloride experiments. The optimal 2 wt% B-rGO/ZnFe2O4 heterojunction exhibits the highest photocatalytic performance, i.e. 84% of Cr(vi) reduction in 90 min under 20 W LED light irradiation with a rate constant of 0.0207 min-1, which was 4.6- and 2.15-fold greater than that of ZnFe2O4 (ZnF) and B-rGO, respectively. The intimate interfacial contact, excellent photon-harvesting properties, effective exciton segregation and availability of active electrons are some factors responsible for enhanced photocatalytic Cr(vi) reduction. In order to fulfill the demand of applied waste-water management, the influences of various photocatalyst amounts, pH values and co-exiting ions on photocatalytic activities were evaluated. Finally, this work provides a way to fabricate S-scheme-based p-n-heterostructures for photocatalytic wastewater treatment.

Full-spectrum Bi@SrTiO3 for bi-directional promotion effects on photocatalytic redox reaction: Insight into intermediates and mechanism

The development of full-spectrum photocatalysts active in the near-infrared (NIR) region has gained increasing attention for deleterious pollutant removal. The integration of plasmonic metals with semiconductors is an effective way to widen the light response range of photocatalysts due to the strong light absorption and fast plasmonic energy transfer of the localized surface plasmon resonance (LSPR). In this work, the full-spectrum responsive Bi@SrTiO3 was prepared via facile solvothermal chemical reduction. The optimal Bi@SrTiO3 achieves exceptional photocatalytic Cr(VI) reduction efficiency and tetracycline degradation, realizing bi-directional promotion effects on redox reaction. According to density functional theory (DFT) simulations, the extraordinary photocatalytic performance is attributed to the tunable built-in electric field (IEF) of the Ohmic contact. The favorable adaptability in real water and high stability of BSTO-25 were proved by experimental results. And the possible photocatalytic mechanism was proposed based on theoretical calculation and experimental results. Furthermore, the non-toxicity of the BSTO-25 was evaluated by E.coli cultivation, which further proves the feasibility of treating wastewater with BSTO-25. This work provides a new perspective on constructing full-spectrum-driven photocatalysts for applications dealing with environmental remediation.

NiFe Layered Double Hydroxides with Controlled Composition and Morphology for the Efficient Removal of Cr(VI) from Water.

A layered double hydroxide (LDH) composed of Ni2+ and Fe3+ with a Fe3+/(Ni2+ + Fe3+) ratio of 0.05, which is not commonly available, was successfully prepared by coprecipitation from an aqueous solution of glycerol containing nickel nitrate and iron nitrate. Precipitation using NaOH as a precipitating agent at room temperature or 120 °C under hydrothermal conditions gave products with micrometer-sized aggregates of nanometer-sized unshaped particles, while that using urea yielded LDHs with a foam-like porous architecture composed of platy particles with a size of 100-300 nm. The products were examined to remove Cr(VI) from an acidic (pH = 3) aqueous solution of K2Cr2O7 by adsorption and photocatalytic reduction. The foam-like porous NiFe-LDH exhibited the highest adsorbed amount (122 mg g-1) and rate (0.017 g mg-1 min-1) in the dark and the highest rate (0.012 min-1) of photocatalytic Cr(VI) reduction among the NiFe-LDHs prepared in the present study, which can be explained as a positive effect of the foam-like porous architecture. These performances were superior to those of other reported LDHs, showing the importance of the composition and the particle morphology to boost the removal of Cr(VI).

Facile synthesis of direct Z-scheme PPy/NH2-UiO-66 heterojunction for enhanced photocatalytic Cr(VI) reduction, industrial electroplating wastewater treatment, and tetracycline degradation

Z-scheme heterojunction photocatalysts generally have excellent redox ability and robust removal efficiency for contaminants in water. Herein, we combined p-type PPy and n-type NH2-UiO-66 by ball milling to prepare a direct Z-scheme PPy/NH2-UiO-66 photocatalyst with ultra-high redox potential. Notably, the optimized efficiency of PPy/NH2-UiO-66 (the mass ratio of PPy to NH2-UiO-66 is 1 wt%, named PPy/NU-1) rapidly reduced Cr(VI) (>95%, 60 min) and TC degradation (>90%, 180 min) at 100 W LED light. Moreover, the PPy/NU-1 has high stability and good anti-interference ability, which can effectively remove Cr(VI) from industrial electroplating wastewater, and the Cr(VI) removal rate is 99%, which meets the industrial wastewater standard and has the potential attraction of actual wastewater treatment. In addition, the techniques of UV-Vis diffuse reflection, electron spin resonance (ESR), photoluminescence (PL), and photoelectrochemical measurement showed that PPy/NH2-UiO-66 composites improved the light capture ability, thereby improving the photocatalytic efficiency. The PPy/NU-1 has a very high redox potential by constructing a Z-scheme heterojunction, enhances the interfacial charge transfer ability, and improves the separation efficiency of photogenerated carriers. Finally, the mechanism of the Z-scheme was systematically by nitroblue tetrazolium (NBT) and p-phthalic acid (TA) transformation, ESR experiments, and density functional theory (DFT) calculations. This work provides a strategy for the preparation of visible photocatalysts with excellent photocatalytic activity and provides new insights for interfacial charge transfer and molecular oxygen activation.

Hydrothermal carbonization carbon induced synthesis of flower-like C/Bi/BiOI heterojunction with heightened photocatalytic Cr(VI) reduction

Modification with metallic Bi and formation heterojunction with carbon material are considered as the compelling strategies to address the shortcoming of bismuth oxyhalide in photocatalytic Cr(VI) reduction. However, the simultaneous and in-situ synthesis of metallic Bi and hydrothermal carbonization carbon (HC) on BiOI to fabricate a ternary heterojunction photocatalyst remains a challenge yet, and the synergistic mechanism between the localized surface plasmon resonance (LSPR) effect and HC is still indistinct. Herein, a ternary heterojunction photocatalyst comprising metallic Bi, HC, and flower-like BiOI was designed and synthesized through the in-situ induction of HC. During the solvothermal synthesis, a portion of Bi3+ was reduced to metallic Bi nanoparticles, and simultaneously gauzy HC was formed. In the ternary heterojunction, the metallic Bi nanoparticles displayed strong LSPR effect, and the coated HC was conducive to transferring photogenerated electrons and enriching Cr(VI). Due to the synergistic effect of metallic Bi and HC, multiple channels for photogenerated carrier transfer were constructed. Deriving from the excellent light-harvesting, accelerated transfer/separation, and restrained recombination of photogenerated carriers, the ternary heterojunction of flower-like C/Bi/BiOI showed superior photocatalytic Cr(VI) reduction. The reaction rate constant of photocatalytic Cr(VI) reduction was about 26 times higher than that of BiOI.

Photocatalytic reduction of chromium(VI) using multiwall carbon nanotubes/bismuth oxide nanocomposite under solar irradiation.

Semiconductor photocatalysis is the most efficient advanced oxidation processes for wastewater treatment. A new carbon-based photocatalyst bismuth oxide/multi-walled carbon nanotube (Bi2O3/MWCNT) nanocomposite has a considerable impact on improving photocatalytic performance. Bi2O3/MWCNTs (BMC) nanocomposite was prepared through the hydrothermal processing with 2.5, 5, 7.5 and 10 wt% of MWCNTs. The preparedphotocatalysts have been thoroughly examined by various techniques. The X-ray diffraction confirmed the prepared photocatalyst as α-Bi2O3 with high crystallinity. The band gap of Bi2O3 and BMC 7.5 nanocomposite was found to be 2.41 and 1.94eV. The prepared photocatalyst revealed smooth and porous merged flower-like structure with respect to the addition of MWCNTs. The model pollutant chromium(VI) (Cr(VI)) has been used to check the reduction efficiency of the prepared photocatalyst under solar irradiation. It was found that BMC 7.5 nanocomposite showed enhanced photocatalytic metal ion reduction (87.48%) compared to pristine Bi2O3 (69.29%). The preliminary photocatalytic Cr(VI) ion reduction experiments were carried to determine the photoreduction efficiency of pristine bismuth oxide and bismuth MWCNT nanocomposite. The kinetic study on Cr(VI) ion reduction obeyed pseudo-first-order rate kinetics for both the prepared photocatalysts. The efficiency of the photocatalysts was further analysed by reusing the same up to 3 cycles without loss of the efficacy.

Efficient visible-light driven photocatalytic Cr(VI) reduction on S and O co-doped g-C3N4 prepared from 2,5-thiophene dicarboxylic acid based macromolecular precursor

Efficient visible-light driven photocatalytic Cr(VI) reduction on S and O co-doped g-C3N4 prepared from 2,5-thiophene dicarboxylic acid based macromolecular precursor

High-efficient charge separation in novel Zn0.5Cd0.5S/Bi4V2O11 heterostructure for boosting photocatalytic Cr (VI) reduction and degradation of tetracycline hydrochloride

Photocatalysis is a green and sustainable technology for the efficient removal of harmful pollutants in water, however, due to the coexistence of multiple pollutants in water system, it is a great challenge to develop multi-functional and efficient photocatalytic systems. Herein, a novel bifunctional Zn0.5Cd0.5S/Bi4V2O11 (ZCS/BVO) heterostructrue photocatalyst was designed and prepared by growing Zn0.5Cd0.5S nanospheres on the surfaces of Bi4V2O11 disc-like nanoflowers through a facial in-situ hydrothermal method. The as-prepared ZCS/BVO heterostructure showed much more enhanced bifunctional visible-light catalytic activity for Cr (VI) reduction and TCH degradation compared with pure Zn0.5Cd0.5S and Bi4V2O11. Among ZCS/BVO samples, ZCS/BVO-10 possessed the best Cr (VI) reduction performance of 86.7 % in 60 min, which was 1.38 and 9.96 times of Zn0.5Cd0.5S and Bi4V2O11. Moreover, ZCS/BVO-10 heterostructure also showed excellent TCH degradation ability of 80.3 % in 48 min, about 2.38 and 3.20 times as high as those of Zn0.5Cd0.5S and Bi4V2O11. The synergistic effect between Zn0.5Cd0.5S and Bi4V2O11 and the close contacted ZCS/BVO heterostructure greatly favored TCH degradation and Cr (VI) reduction reactions due to the increased surface area, enhanced light absorption and boosted charge separation. From the cyclic experiment, ZCS/BVO exhibited high stability and reusability. This work undoubtedly provided a multi-functional and effective photocatalyst for treating various pollutants in water bodies.

Facile preparation of high-performance hydrochar/TiO2 heterojunction visible light photocatalyst for treating Cr(VI)-polluted water

In order to remedy the shortcomings of narrow absorption wavelength range and low photogenerated carrier separation efficiency of TiO2 photocatalyst, hydrochar (HC) was chosen to modify TiO2 by constructing HC/TiO2 heterojunction composite. HC/TiO2 composites were synthesized from glucose, tetrabutyl titanate and deionized water by a simple one-pot hydrothermal way, and their photocatalytic Cr(VI) reduction properties were studied. The results indicated that HC/TiO2 composites had tremendously improved photocatalytic Cr(VI) reduction activity, in comparison with TiO2, HC and a number of newly reported TiO2-based visible light photocatalysts. When the mass percentage of glucose to tetrabutyl titanate was 14, the obtained HC/TiO2-2 possessed the maximal photocatalytic activity, which was 19 times that of TiO2 and 14.3 times that of HC under visible light (wavelength > 420 nm) irradiation, and 3.2 times that of TiO2 under ultraviolet-visible light (Xenon lamp) irradiation. Furthermore, the photocatalytic stability of HC/TiO2-2 was also excellent. Additionally, proper choice of the photocatalysis experiment parameters could further raise the photocatalytic Cr(VI) reduction efficiency of HC/TiO2-2. The exceptionally elevated photocatalytic activity of HC/TiO2-2 was found to be due to its type-II heterojunction structure, which drastically heightened the separation and transfer efficiencies of photogenerated electrons and holes. Besides, HC/TiO2-2 also showed great potential for practical application in photocatalytic treatment of the Cr(VI) effluents discharged from freezing brine and black chromium plating industries.

NiCoP as a cocatalyst decorating CdIn2S4 for enhanced photocatalytic performance under visible light: DFT calculation and mechanism insight

Solar photocatalysis, a green and sustainable technology, can effectively address the global energy shortage and environmental pollution. Herein, CdIn2S4 (CIS) microflowers and NiCoP (NCP) nanoparticles were prepared by hydrothermal synthesis and vacuum calcination, respectively. Subsequently, novel NiCoP/CdIn2S4 (abbreviated x wt % NCP/CIS; x = 7, 9, 11, 13, and 15) composite photocatalysts were synthesized using an impregnation method. The as-obtained NCP/CIS catalysts exhibited excellent photocatalytic activities for hydrogen production and Cr(VI) reduction with high cycling stability under visible light (λ > 420 nm). The H2 production rate of the optimal 11% NCP/CIS sample was 651.67 μmol g−1 h−1, which was approximately 25.92 times higher than that of individual CIS (25.14 μmol g−1 h−1). The apparent quantum efficiency at 420 nm reached 3.31%. The rate constant of photocatalytic Cr(VI) reduction reached 0.036 min−1, 2.77 and 11.19 times that of CIS (0.013 min−1) and NCP (0.0032 min−1), respectively. The enhanced photocatalytic properties of NCP/CIS are attributed to the improved visible-light absorption and efficient separation of photoinduced carriers. Furthermore, free radical capturing tests and ESR data proved that e− and ·O2− were responsible for Cr(VI) reduction. The electron transfer pathway and photocatalytic mechanism were verified using X-ray photoelectron spectroscopy, density functional theory calculations, and energy band structures. This study provides novel approaches for designing and preparing non-noble metal cocatalyst/semiconductor systems with remarkably efficient photocatalytic performance for Cr(VI) removal and H2 generation.

Conjugated organic component-functionalized hourglass-type phosphomolybdates for visible-light photocatalytic Cr(VI) reduction in wide pH range

Conjugated organic component-functionalized hourglass-type phosphomolybdates for visible-light photocatalytic Cr(VI) reduction in wide pH range

Simple preparation of polyaniline/SiC composite as an efficient photocatalyst for the reduction of Cr(VI)

In order to enhance the photocatalytic activity of SiC, polyaniline (PANI) was utilized to modify it by constructing PANI/SiC heterojunction composite. PANI/SiC heterojunction composite was prepared via first mixing of SiC and PANI in solution and subsequent evaporation of the solvent. The photocatalytic performance of the as-prepared PANI/SiC composite in the reduction of Cr(VI) under xenon lamp irradiation was tested. The results indicated that combination with PANI can dramatically improve the photocatalytic activity of SiC. The as-prepared PANI/SiC composite not only had a photocatalytic activity 6.2 times as that of SiC, but also was more efficient than many recently reported photocatalysts in photocatalytic reduction of Cr(VI). Based on the adsorption and photoelectrochemical analysis results, it was deduced that the superior photocatalytic activity of PANI/SiC composite was attributed to its larger Cr(VI)-adsorbing capacity, higher light-absorbing ability, and more efficient separation and transfer of photogenerated electrons (h+) and holes (e–). Considering its simple preparation and excellent photocatalytic Cr(VI) reduction activity, the PANI/SiC photocatalyst is hopeful for practical application in Cr(VI) effluent treatment.

Development of C3N4 embedded Bi2WO6 heterostructure for the improved toxic Cr(VI) reduction performance

C3N4 embedded Bi2WO6 hierarchical microsphere was successfully synthesized in this study using a simple hydrothermal approach and characterized using sophisticated instruments. In comparison to C3N4 and Bi2WO6 systems, the C3N4 embedded Bi2WO6 system exhibits excellent photocatalytic Cr(VI) reduction activity after 150 min of UV–vis illumination. The remarkable efficiency of the fabricated photocatalyst can be ascribed to the creation and electronic contact between Bi2WO6 with C3N4, thereby enhancing its charge transfer by the increased surface active sites. Our research demonstrates a simple and successful method for fabricate an effectual catalyst for the effective reduction of Cr (VI).

Enhancing Photocatalytic Cr(VI) Detoxification and N2 Fixation through Construction of a Z-Scheme Heterojunction via Partial Derivatization of BiOBr on the MOF-808/Bi-BDC Composite

Enhancing Photocatalytic Cr(VI) Detoxification and N₂ Fixation through Construction of a Z-Scheme Heterojunction via Partial Derivatization of BiOBr on the MOF-808/Bi-BDC Composite

Enhanced photocatalytic Cr(VI) reduction performance by novel PDI/COFs composite

Constructing the heterojunction by using covalent organic frameworks (COFs) is an effective way to promote photocatalytic activity. Herein, we designed and constructed different ratios of PDI/COFs hybrid materials by solvothermal method, denoted as PDI/TAPB-PDA (TAPB = 1,3,5-tris(4-aminophenyl)benzene, PDA = terephthaldehyde) composite. Although the construction of the heterojunction can destroy the long-range order of the TAPB-PDA COF structure to varying degrees, it does not affect the photocatalytic performance of PDI/TAPB-PDA composite. The optimal composite PDI/TAPB-PDA-5 with an initial molar ratio of PDI to TAPB-PDA COF of 32:1 has the highest photocatalytic performance for Cr(VI) reduction. The fitted first-order kinetic reaction rate k of PDI/TAPB-PDA-5 was 12.3 and 3.6 times that of PDI and TAPB-PDA COF, respectively. The superior photocatalytic activity of PDI/TAPB-PDA composite can be attributed to the broadened light absorption range and enhanced separation and transfer of carriers. The construction of composite materials between imine-linked COFs and dye PDI with excellent photocatalytic performance provides the possibility and affordability for realizing the practical application of expensive COFs-based catalysts.

A novel tungsten diselenide nanoparticles for enhanced photocatalytic performance of Cr (VI) reduction and ciprofloxacin (CIP)

Nanoparticles (NPs) fabrication is a significant approach to enhance the visible light response of photocatalysts, to realize inexpensive and more harmful compound removal, at larger scale. The poor electrons and holes separation capability and low light activity of bulk materials can be notably enhanced through developing NPs. From photocatalytic investigation, better performance was received in the tungsten diselenide (WSe2) NPs than that in bare WSe2, exhibiting the action of restrained recombination of charge carriers in the NPs. The photocatalytic Cr(VI) reduction efficiency of WSe2 NPs is 2.7 folds greater than that by bare WSe2. On the other hand, the photocatalytic efficiency follows the order of nano WSe2-3 > nano WSe2-2 > nano WSe2-1 > bare WSe2, nano WSe2-3 is nearly 2.7 folds greater than that of bare WSe2. The results imply the fabrication of WSe2 NPs and it possesses improved visible light utilization. The proposed WSe2 NPs have merged with the three aspects of photocatalytic capability including the visible light activity, the valid separation of photo-response charge carriers and enough surface active sites owing to the nanoscale formed. This research endows conduct on the potential style of NPs for photo-response water environmental remediation.

Construction of UiO-66-NH2 decorated by MoS2 QDs as photocatalyst for rapid and effective visible-light driven Cr(VI) reduction

The photoactive metal-organic frameworks (MOFs) are good candidates for photocatalysts, but the quick electron-hole pairs recombination has greatly restricted the photocatalytic ability of MOFs. To improve the photoactivity of MOFs, MOFs-based composite materials have been extensively studied. Here, we successfully integrated MoS2 quantum dots (QDs) with UiO-66-NH2 for the first time under hydrothermal conditions. The as-prepared MoS2 QDs/UiO-66-NH2 (MS-U) had good visible light response ability (absorption edge at 445 nm), and charge separation and transfer ability, which lays the foundation for the photocatalytic Cr(VI) reduction. Photocatalytic studies revealed that MoS2 QDs-5/UiO-66-NH2 (MS-U-5) had superior Cr(VI) reduction activity than pure MoS2 QDs and UiO-66-NH2. MS-U-5 could remove 98% Cr(VI) at pH= 2 with visible light irradiation for 20 min, which is the fastest visible light driven Cr(VI) reduction rate among the reported MOFs-based composite photocatalysts without the presence of any cocatalysts or scavengers as far as we know. Importantly, MS-U-5 could be reused at least three times. In the end, the possible electron transfer path and mechanism of Cr(VI) reduction was also investigated.

Synergy of Adsorption and Photocatalytic Reduction for Efficient Removal of Cr(VI) with Polyvinylidene Fluoride@Polyvinyl Alcohol-FeC2O4/Bi2.15WO6.

Although the photocatalytic reduction of Cr(VI) to Cr(III) by traditional powder photocatalysts is a promising method, the difficulty and poor recovery of photocatalysts from water hinder their wide practical applications. Herein, we present that FeC2O4/Bi2.15WO6 (FeC2O4/BWO) composites were tightly bonded to modified polyvinylidene fluoride (PVDF) membranes by chemical grafting with the aid of polyvinyl alcohol (PVA) to form photocatalytic composite membranes (PVDF@PVA-FeC2O4/BWO). The contact angle of PVDF@PVA-FeC2O4/BWO (0.06 wt % of FeC2O4/BWO) is 48.0°, which is much lower than that of the pure PVDF membrane (80.5°). Meanwhile, the permeate flux of 61.43 g m-2 h-1 and water flux of 250.60 L m-2 h-1 were observed for PVDF@PVA-FeC2O4/BWO composite membranes. The tensile strength of composite membranes reached 48.84 MPa, which was 9.8 times higher than that of PVDF membrane. It was found that the PVDF@PVA-FeC2O4/BWO membrane exhibited excellent photocatalytic Cr(VI) reduction performance under both simulated and real sunlight irradiation. The adsorption for Cr(VI) by PVDF@PVA-FeC2O4/BWO can reach 47.6% in the dark process within 30 min, and the removal percentage of Cr(VI) could reach 100% with a rate constant k value of 0.2651 min-1 after 10 min of light exposure, indicating a synergistic effect of adsorption and photoreduction for Cr(VI) removal by the composite membrane. The PVDF@PVA-FeC2O4/BWO membrane had good stability and reusability after seven consecutive cycles. Most importantly, the influences of foreign ions on Cr(VI) reduction were investigated to mimic real sewage, which revealed that no obvious adverse effects can be found with the presence of common foreign ions in sewage. The photocatalytic membrane material developed in this study provides a new idea for treating Cr(VI)-containing wastewater and has a more significant application prospect.

Study on Photochemical Properties of a Sr-SnS2/CaIn2S4 Heterostructure to Improve Cr(VI) Removal.

Compound semiconductor photocatalysis technology is considered to be a promising treatment for solving water problems efficiently. The point of designing high-efficiency catalysts is to optimize the band gap structure and facilitate the separation of charge carriers by establishing new electron migration pathways. Recently, 3D porous CaIn2S4 was found to have good photocatalytic ability. However, the quick recombination and agglomeration of carriers still limit its application. Herein, we prepared a heterostructure by introducing 2D Sr-doped SnS2 to 3D CaIn2S4 by a hydrothermal synthesis method. The optimal dosage of Sr-SnS2 is 3%, and the photocatalytic Cr(VI) removal efficiency of 3% Sr-SnS2/CaIn2S4 (SSCS-3) is 5.82 and 10.83 times those of pure CaIn2S4 and SnS2, respectively. According to the results of characterization tests and calculation verification, we inferred that the enhanced photocatalytic removal of Cr(VI) is due to the introduction of Sr-SnS2 that can promote the rapid transfer of photogenerated electrons to the surface of CaIn2S4, and the heterostructure formed between 2D Sr-SnS2 and 3D CaIn2S4 can also provide abundant reaction sites. The promotion of carrier separation is mainly due to the formation of a built-in electric field of the Sr-SnS2/CaIn2S4 heterostructure. This work provides new ideas and technologies for the treatment of Cr(VI) in wastewater.

F-doped Bi2WO6 with rich oxygen vacancies for boosting photo-oxidation/reduction activity

The erythrocyte-like F-doped Bi2WO6 (F-Bi2WO6) with rich oxygen vacancies was fabricated via a simple one-step hydrothermal method. With the help of various characterization techniques, it was determined that F− anions were doped into the Bi2WO6 lattice together with the generation of oxygen vacancies in the doping process. The oxygen vacancy as an electron acceptor in Bi2WO6 could tune band structure and trap the electrons easily to generate a new quick channel of electron transport, thus promoting the separation and transfer of e−-h+ pairs. The F-Bi2WO6 photocatalysts exhibited superior properties in photocatalytic activity, photocarrier separation and visible-light absorption compared with the pristine Bi2WO6. And the optimized F1.00-Bi2WO6 displayed a remarkable 1.6 and 2.5 times enhanced photocatalytic Cr(VI) reduction and MO degradation activities than the pristine Bi2WO6, respectively. Consequently, the enhanced photocatalytic mechanisms were elaborated for the Cr(VI) reduction and MO degradation under visible-light, respectively.