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BiVO4 and g‐C3N4 have gain attention for their potential in sustainable energy and environmental applications due to their visible light absorption properties. However, their limitations in terms of visible light absorption and electron‐hole separation have prompted efforts to enhance their energy utilization and reduce electron‐hole recombination. In our study, we investigated the fabrication of a ternary Ag/g‐C3N4/BiVO4 composite for Rhodamine B (RhB) degradation under visible light irradiation using a combination of photo‐deposition and calcination methods. Our findings demonstrate that the Ag/g‐C3N4/BiVO4 outperforms g‐C3N4, BiVO4, and g‐C3N4/BiVO4 in terms of RhB degradation rate. This improvement can be attributed to the improved light absorption and synergetic effects on charge transfer and photoelectron‐hole recombination resulting from the incorporation of Ag into the ternary system. This ternary Ag/g‐C3N4/BiVO4 composite has potential as a photocatalyst for the removal of organic pollutants due to its reasonable design and superior effectiveness. [ABSTRACT FROM AUTHOR]

Pollution of waste and natural waters by antibiotics is a major health issue that induces the development of resistant pathogens. Pollutant may be removed by photocatalysis, yet classical photocatalysis is limited by the short carrier lifetime. Here, we review multicomponent photocatalysts for the synergic degradation of antibiotics. Components include metallic nanoparticles, semiconductors and adsorbents. The synergy of these components provide photocatalysts with advantages such as extended visible-light range with bandgap energy lower than 2.8 eV, improved charge transfer properties, enhanced adsorption capacity and more active reaction sites. The removal of the antibiotics, based on the decrease of the initial concentration, reaches 80–100%, but mineralization is rarely measured in reports. Proposed mechanisms for the photocatalytic degradation of antibiotics over single and multicomponent photocatalysts are discussed. [ABSTRACT FROM AUTHOR]

The effects of the substitution of V5+ with Ni2+ at the corresponding sites in BiVO4 on the crystal structures, optical properties, and photocatalytic efficiency of BiVO4 was investigated. Ni2+ cations doped at the V5+ sites in BiVO4 was confirmed by X-ray diffraction, Raman, X-ray photoelectron spectroscopy, ultraviolet–visible diffuse reflectance spectra, and photoluminescence spectra. Ni-doped BiVO4 exhibited excellent degradation of crystal violet (CV) compared with the bare BiVO4. For optimal Ni2+ doping of 5%, the degradation rate of CV, which reached about 95% within 180 min of LED light irradiation, was obtained. Ni doping can introduce advantageous defect states that significantly increase the separation and diffusion efficiency of the photo-induced charge carriers, thereby boosting the photocatalytic activity of crystal structures. [ABSTRACT FROM AUTHOR]

Nano Fe-BTC/graphene oxide (GO) composites were successfully synthesized by hydrothermal treatment with a microwave-assisted method. Samples were characterized by X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), N2 adsorption–desorption, Scanning electron microscopy (SEM), Energy-dispersive X-ray spectroscopy (EDS), and Ultraviolet–visible diffuse reflection spectroscopy (UV–Vis DRS). SEM image of Fe-BTC/GO-30 showed the particle size of 30–50 nm on the GO surface. From the UV–Vis diffuse reflectance spectra, it revealed that nano Fe-BTC/GO composite absorbed the wavelengths in the visible light region with a low bandgap energy of 2.2–2.45 eV. Fe-BTC/GO nanocomposites were tested for the photocatalytic degradation of reactive yellow 145 (RY-145) in aqueous solution. Fe-BTC/GO composites exhibited high photocatalytic activity. Thus, at pH of 3 and high initial concentration of 100 mg RY-145/L, removal efficiency reached the value of 98.18% after 60 min. of reaction. In comparison with Fe-BTC/GO synthesized by the solvothermal method, nano Fe-BTC/GO showed much higher RY-145 removal efficiency. Moreover, this Fe-BTC/GO-30 showed high catalytic activity stability and could be reused, opening the high potential application of this promising photo-Fenton catalyst in photocatalytic degradation of organic pollutants from aqueous solution. [ABSTRACT FROM AUTHOR]

BACKGROUND The development of visible light photocatalysts for CO2 reduction into methanol is a challenge, as most of the reported photocatalysts can only work in a UV light environment. Slow kinetics and poor selectivity of CO2 towards methanol are currently two significant drawbacks limiting the practical application of CO2 reduction into methanol. RESULTS: A ZnFe2O4/TiO2 heterojunction with a ratio of unity was found to lead to the highest methanol yield of 693.31 μmol (g cat)−1 under a light intensity of 100 mW cm−2. This photocatalyst also possessed the highest BET surface area of 6.5211 m2 g−1 and better morphological structure, as compared with other ratios (1:2, 2:1 w/w). Interestingly, a loading of 1 g L−1 of ZnFe2O4/TiO2 (1:1) heterojunction photocatalyst in the pre‐annealing treatment of ZnFe2O4 at 900 °C and post‐annealing treatment of ZnFe2O4/TiO2 (1:1) composite at 500 °C revealed that there was an enhancement in the interfacial interaction, and subsequently an efficient photoreduction of CO2 into methanol. CONCLUSIONS: This study demonstrates facile fabrication of p–n heterostructured phototcatalysts for reduction of CO2 with marked improvement in methanol yield under visible light irradiation. It provides a viable route for exploring the effects of composition, hydrothermal treatment, and pre‐/post‐annealing treatment of hybrid semiconductor composites used to scale up photocatalytic CO2 conversion in solar fuel‐based devices. [ABSTRACT FROM AUTHOR]

Abstract The development of composite photocatalyst is a promising direction for improving photocatalytic performance of decomposition of organic dyes. This study aimed to fabricate two composite photocatalysts using either Fe 3 O 4 or NiFe 2 O 4 with MIL-53(Fe) as heterogeneous catalysts for the degradation of rhodamine B (RhB) under visible light irradiation by a 40 W compact fluorescent lamp. The physicochemical, the surface, the magnetic and the energy band gap of the photocatalyst were characterized by XRD, FT-IR, Raman, FE-SEM, UV–vis DRS, Brunauer–Emmett–Teller (BET), and VSM. From the photocatalytic activities test results, the NiFe 2 O 4 -doped MIL-53(Fe) sample expressed a higher photocatalytic degradation capacity of RhB than that of Fe 3 O 4 /MIL-53(Fe) sample, significantly better than that of the bare of Fe 3 O 4 , NiFe 2 O 4 , and MIL-53(Fe). [ABSTRACT FROM AUTHOR]

We synthesized BiVO 4 photocatalysts using a facile solvothermal router and three different mixed solvents, 2-methoxyethanol (MEOH), 1,2-ethanediol (EDOH), and 1,2,3-propanetriol (PTOH) with water, which we then characterized by XRD, XPS, FE-SEM, and UV–vis DRS. The XRD results show that we obtained single-phase monoclinic scheelite (m-s BiVO 4) in the EDOH/water and PTOH/water systems and monoclinic/tetragonal heterostructure BiVO 4 (m-t BiVO 4) in the MEOH and water mixture. m-t BiVO 4 with a monoclinic/tetragonal heterostructure prevents the recombination of photoexcited electron-hole pairs. As such, of the three samples, the m-t BiVO 4 material showed the highest activity in the photodecomposition of rhodamine B. Unlabelled Image • A solvothermal router was use to control the morphology and phase structure of BiVO 4. • m-s BiVO 4 was obtained in the ethane-1,2-diol/water or propan-1,2,3-triol/water. • m-t heterostructure BiVO 4 was obtained in 2-methoxyethanol/water. • Heterostructure was more effective than m-s phases in RhB degradation under visible-light. • Heterojunctions could hinder the recombination of photoexcited electron-hole pairs. [ABSTRACT FROM AUTHOR]

[Display omitted] • Bismuth based MOFs were synthesized by the microwave-assisted solvothermal method. • Bi-TATB showed a high specific surface area. • Bi-TATB showed excellent photocatalytic activity (k = 32.1 × 10−3 min−1). • The mechanism of RhB photodegradation process over Bi-MOF was investigated. • Bi-TATB showed excellent photocatalytic O 2 evolution. In this study, we studied the effect of starting ligands such as 1,4-benzenetdicarboxylic (H 2 BDC), 1,3,5-benzenetricarboxylic (H 3 BTC), and 4,4′,4″-s-triazine-2,4,6-triyl-tribenzoic (H 3 TATB) acids on the photocatalytic activity of three bismuth-based MOFs (Bi-MOF) obtained via a microwave-assisted solvothermal process. Different shapes and sizes of ligands displayed different structure properties from the corresponding Bi-MOF. Specifically, Bi-MOF composed of Bi3+ and H 3 TATB (Bi-TATB) exhibits the largest specific surface area of 355 m2/g, highest surface-oxygen vacancy amount, a more vigorous light absorption intensity with a broader range of visible light absorption and red-shifted absorption edge than that of Bi-MOF composed of Bi3+ and H 2 BDC (Bi-BDC) and Bi-MOF composed of Bi3+ and H 3 BTC (Bi-BTC), suggesting the extension in the photocatalytic activity for Bi-TATB. The reason is attributed to the difference in their structural features. Compared with H 2 BDC and H 3 BTC ligands in Bi-BDC and Bi-BTC, H 3 TATB ligands in the structure of Bi-TATB contained more delocalized π electrons. This outcome may facilitate the ligand-to-metal charge transfer (LMCT) and decrease the electronic bandgap of the Bi-TATB, thus contributing to the enhanced photocatalytic rate. The enhanced photocatalytic activity of Bi-TATB was further confirmed by the photodegradation of rhodamine B (RhB) under LED light irradiation, which is 99.1% of RhB removal after 180 min of light irradiation. The as-synthesized Bi-TATB showed promising photocatalytic activity for the degradation of organic dye with an excellent recyclable catalytic efficiency. With the above understanding, Bi-MOF was finally used for the photocatalytic O 2 evolution from water under LED light irradiation. The Bi-TATB had a maximum photocatalytic O 2 evolution rate of 691 μmol h−1. To the best of the author's knowledge, there has been no research on both the photocatalytic degradation of organic model dye pollutants and photocatalytic O 2 evolution studies using Bi-MOFs with different organic linkers. The results should open an alternative approach of ligand selection that could increase the applicability of Bi-MOF in the field of catalysis. [ABSTRACT FROM AUTHOR]

Ag x -Zn 100−x -BTC/GO composites (BTC: benzene-1,3,5-tricarboxylic, GO: graphene oxide) with different Ag/Zn molar ratios were synthesized using microwave-assisted hydrothermal treatment. The Ag x -Zn 100−x -BTC/GO exhibited excellent photocatalytic performance in the reactive yellow 145 dye (RY-145) degradation under irradiation of visible light with nearly 100% of RY-145 removal after 35 min, as compared to Zn-BTC/GO and Ag-BTC/GO. Reactive oxygen species scavenging assays have shown that the holes (h+) and superoxide radical anion (O 2 −•) play a primary role in RY-145 degradation. Based on the band structure of materials, the Z-scheme photocatalytic mechanism was suggested. The effect of catalyst dosage, pH and dye concentration on the efficiency of photocatalytic activity of bimetallic Ag 50 -Zn 50 -BTC/GO was also investigated. The improvement in photocatalytic activity of bimetallic Ag 50 -Zn 50 -BTC/GO could be given by the synergism of (i) absorption of visible light confirmed by UV-Vis diffuse reflectance spectra; (ii) the increased lifetime as evidenced by photoluminescence spectra and transient photocurrent response; (iii) the increased oxygen vacancy defects as confirmed by X-ray photoelectron spectroscopy results. The degradation pathway of RY-145 dye was also predicted based on liquid chromatography-mass spectrometer analysis. The removed chemical oxygen demand, biological oxygen demand, total organic carbon outcomes indicated the high mineralization ability for RY-145 degradation over Ag 50 -Zn 50 -BTC/GO. [Display omitted] • Microwave-assisted synthesis of Ag x -Zn 100−x -BTC/GO composites was investigated. • The Ag 50 -Zn 50 -BTC/GO could degrade nearly 100% RY-145 within 35 min • The Ag 50 -Zn 50 -BTC/GO exhibits high mineralization ability for RY-145 degradation. • The degradation pathways of reactive yellow 145 were deduced from LC-MS analysis. • This improvement is due to bimetallic Ag/Zn in the SBU network. [ABSTRACT FROM AUTHOR]

[Display omitted] • The concept of developing photocatalytic carbon dioxide (CO 2) reduction is proposed. • Renewable fuels production and the CO 2 reduction are simultaneously provided. • Recent advances with more insights are discussed for enhancing the efficiency. • Light-driven renewable fuels and their reaction pathways are highlighted. • Critical challenges and prospects are systematically presented. The concept of photocatalytic reduction of carbon dioxide (CO 2) into solar fuels has received considerable attention. This approach could resolve the environmental issue and the energy crisis synergistically. In this study, several possible products and reaction pathways of CO 2 reduction that might happen under different conditions are summarized. Various photocatalysts and their mechanism for the reduction of CO 2 into C 1 and C 2+ products are highlighted and overviewed. In addition, we address the yet unresolved questions concerning the insight of the mechanism and tailoring photocatalysts, which can bring more insights for enhancing photocatalytic efficiency. Finally, we provide the remaining challenges and prospects for the development of photocatalytic CO 2 reduction. [ABSTRACT FROM AUTHOR]