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• The novel biochar decorated Bi 4 O 5 Br 2 /g-C 3 N 4 heterojunction is fabricated. • Bi 4 O 5 Br 2 /g-C 3 N 4 /C heterojunction can effectively degrade norfloxacin. • Enhanced ability is ascribed to the synergistic effect of adsorption- photocatalytic. • Charge separation efficiency is significantly improved by the S-scheme model. • The effect factors, active species, intermediates and mechanism were studied. In this work, a novel biochar decorated Bi 4 O 5 Br 2 /g-C 3 N 4 S-scheme heterojunction was successfully prepared for Norfloxacin (NOR) degradation, and it was found that the 5 %-Bi 4 O 5 Br 2 /g-C 3 N 4 /C heterojunction exhibited the excellent photocatalytic degradation activity toward NOR, degrading 92.5 % of NOR within 72 min under visible light irradiation. The effects of pH, dosage, and concentration of the NOR on the photocatalytic activity were also systematically investigated. The mechanism studies revealed that the active species like hole (h +), hydroxyl radical (·OH), and superoxide radical(·O 2 –) play a predominant role in the NOR degradation, and the enhanced removal rate of Bi 4 O 5 Br 2 /g-C 3 N 4 /C heterojunction can be attributed to the synergistic effect of adsorption and photocatalytic process. In addition, an S-scheme transfer channel in the interface of the Bi 4 O 5 Br 2 /g-C 3 N 4 /C heterojunction is proposed, which can effectively improve the separation of the photogenerated carriers and enhance the photocatalytic performance. This research provides inspiration for designing S-scheme heterojunction for wastewater treatment. [Display omitted] [ABSTRACT FROM AUTHOR]

• The adhesion of V/N-TiO 2 to the honeycomb ceramics leads to real-time continuous and near-complete photodegradation removal of toluene due to the synergistic effect. • The catalyst shows excellent cyclic stability and can be reused. • The overall performance of this V/N-TiO 2 @HC flow photoreactor is among the highest compared with state-of-the-art technologies. Photocatalytic degradation of volatile organic compounds (VOCs) is a significant applying aspect of photocatalysis. Both the modulation of photocatalysts and the rational dispersion of them on supports are key for solar-driven VOC degradation. Conventional batch-type photoreactors have low efficiency while continuous-flow photoreactors suffer from the problem of incomplete removal of VOCs. Herein, aiming for continuous and complete degradation of toluene gas as the target contaminant, continuous-flow photocatalytic degradation reactors were made by adhering the vanadium and nitrogen codoped TiO 2 on honeycomb ceramics (V/N-TiO 2 @HC) by a simple sol-gel method. In such a reactor, the rich ordered pores in the HC accelerate mass transport of toluene, and the introduction of V/N dopants narrows the bandgap and widens the light absorption range of TiO 2 , together resulting in continuous and nearly-complete photocatalytic degradation of toluene. The unique and stable structure of HC allows the photocatalysts to be reused. The degradation rate of toluene gas can reach 97.8%, and after 24 rounds of photocatalytic degradation, there is still a degradation rate of 96.7%. The impacts of loading times and gaseous flow rate on the photocatalytic performance of V/N-TiO 2 @HC are studied in detail. Our study provides a practical solution for the continuous and complete photocatalytic degradation of VOCs and opens a new application field for HC. This work reports the continuous-flow photocatalytic degradation reactors using vanadium and nitrogen-codoped TiO 2 coated on honeycomb ceramics (V/N-TiO 2 @HC) by a simple sol-gel method. These reactors effectively degraded toluene gas with a nearly complete degradation rate of 97.8%, providing a practical solution for the volatile organic compounds. [Display omitted] [ABSTRACT FROM AUTHOR]

• Bi 2 O 2 S/NiFe 2 O 4 photocatalyst with strong interface interaction was constructed. • Bi 2 O 2 S/NiFe 2 O 4 shows excellent photocatalytic activity on TC degradation. • The interfacial engineering accelerates the charge direction transfer process. • Bi 2 O 2 S/NiFe 2 O 4 can generate holes and ·O 2 − efficiently via S-scheme mechanism. Heterojunction photocatalysts have shown considerable activities for organic pollutants degradation. However, the faint connection interface and inferior charge shift efficiency critically block the property of heterojunction photocatalysis. Herein, Bi 2 O 2 S/NiFe 2 O 4 nanosheets heterojunction with ultrastrong interface interaction and high internal electric field are designed by an in-situ growth method. Tentative and theoretical consequences prove that the interfacial interaction and internal electric field not only act as the electron flow bridge but also decrease the electrons shift energy obstacle, thus speeding up electrons transfer and achieving effective spatial electron-hole separation. Therefore, a large amount of ·O 2 – and holes as active species were generated. Remarkably, Bi 2 O 2 S/NiFe 2 O 4 establishes a considerably boosted photocatalytic performance for tetracycline degradation (0.032 min–1), which is about 14.2-fold and 7.8-fold of the pristine BOS and NFO, respectively. This work provides a promising motivation for modulating charge transfer by interface control and internal electric field to boost photocatalytic performance. [Display omitted] [ABSTRACT FROM AUTHOR]

• A dual-functional nanofibrous membrane material was prepared for wastewater remediation. • The adsorption facilitated and accelerated the photocatalytic degradation reaction. • The photocatalysis regenerated the adsorption active site and realized green recycle. • The synergistic effect of adsorption and photocatalysis was investigated systematically. • The synergy produced a "1+1>2" effect for highly efficient removal of pollutants. Adsorption and photocatalysis are regarded as two desirable technologies for wastewater remediation, but are still unsatisfactory in removal effect, eco-friendly regeneration and facile reusability. In this study, we developed a composite nanofibrous membrane material with excellent removal performance for organic pollutants based on synergistic adsorption and photocatalysis. A novel boron-doped, nitrogen-deficient graphitic carbon nitride (B-C 3 N 4) photocatalyst as well as an amphiphilic copolymer of methyl methacrylate and acrylic acid (p(MMA-AA)) were synthesized respectively, and then used to modify polyethersulfone for the fabrication of composite nanofibrous membrane with improved hydrophilicity, negatively-charge property and enhanced visible light response simultaneously. Subsequently, the synergistic effect of adsorption and photocatalytic degradation for organic pollutants were identified especially and resulted in an excellent removal efficiency even superior to the combination of adsorption and photocatalytic degradation, which could be called a "1+1>2" effect. In addition, the regeneration and reusability, the purification ability for multicomponent wastewater, and the photocatalytic mechanism, were investigated and discussed systematically. In this work, we not only prepared the nanofibrous membrane with synergistic effect of adsorption and photocatalysis, but also provided a versatile approach to design dual-functional support material to ensure the practical applications of powdery photocatalyst in wastewater treatment. [ABSTRACT FROM AUTHOR]

• Icosahedral (Ih) Au@C 60 core-shell is established as a plasmonic photocatalyst. • The enhanced LSPR of Ih Au core coupled with the down-PL of C 60 shell is realized. • The C 60 shell shows excellent photoinduced electron transfer/acceptance capacity. • The optimal photocatalysis of Ih Au@C 60 was achieved under alkaline condition. • The flexible Ih Au@C 60 film shows excellent photocatalytic stability/reusability. The unique hot carrier-driven direct plasmonic photocatalysis of coinage metal nanomaterials (NMs) via energetic localized surface plasmon resonance (LSPR) in visible-light region has been explored in recent years. However, the low photoinduced electron transfer efficiency and insufficient separation of electron-hole pairs would severely preclude their widespread practical applications. Herein, we demonstrate an interesting plasmonic photocatalyst based on the construction of icosahedral (Ih) Au@C 60 core-shell NMs, taking advantage of specific delocalized π electrons structure of a tight C 60 shell and enhanced LSPR property of Ih Au core. Then, the pronounced interfacial interaction at junction region endows the obtained Au@C 60 NMs with an outstanding photoinduced hot carrier-transmission during photocatalytic reaction, facilitating a remarkably higher (1.89 times) photocatalytic activity toward visible-light driven degradation of crystal violet (CV) dyes, as compared to bare Au NMs. Impressively, the photocatalytic activity of Ih Au@C 60 NMs can be effectively optimized by changing the pH value of reaction solution, with the kinetic rate constant reaching the maximum value of 0.179 min−1 in pH 0 11.4 solution, while 0.005 min−1 at pH 0 3.0. Moreover, due to the protection of a tight C 60 shell, the Ih Au@C 60 NMs also possess excellent photocatalytic stability/reusability in recycling runs, holding great potential for the design of robust and high-performance plasmonic photocatalysts in repeated practical applications. [Display omitted] [ABSTRACT FROM AUTHOR]

The development of high-efficiency photocatalysts is the primary goal in the field of photocatalytic antibacterial research. In this work, the GaN:ZnO solid solution nanoparticles (NPs) photocatalyst with strong visible absorption and large specific surface area was synthesized via the sol-gel and nitridation reaction process. Also, we systematically investigated the removal efficiency of the organic pollutant and antibacterial activity on E. coli and S. aureus. Notably, methylene blue solution could be completely degraded after 100 min of visible light illumination using 2 mg/mL GaN:ZnO catalyst. Moreover, ~94% of the E. coli were inactivated within 120 min, whereas 100% antibacterial activity against S. aureus was achieved after 90 min of visible light illumination mediated by GaN:ZnO NPs. We further explore the potential mechanism of visible light photocatalytic antibacterial activity enhanced by GaN:ZnO NPs photocatalyst. The current work not only provides a new and efficient photocatalytic antibacterial nanomaterial but also demonstrates its promising applications in environmental and biological fields. • GaN:ZnO solid solution nanoparticle photocatalyst is synthesized by sol-gel and nitridation reaction process. • The photocatalyst demonstrates a good degradation effect on organic pollutants under visible light illumination. • GaN:ZnO nanoparticles can kill ~94% of E. coli after 120 min visible light illumination. • 100% of S. aureus can be inactivated by GaN:ZnO nanoparticles after 90 min visible light illumination. • The antibacterial activity of GaN:ZnO nanoparticles is derived from the ROS produced by photocatalytic process. [Display omitted] [ABSTRACT FROM AUTHOR]

• This review summarizes the recent advances in the design and synthesis of crystalline carbon nitride. • A variety of synthetic methods for preparing crystalline carbon nitride are introduced. • We highlight the modification methods of crystalline carbon nitride for promoting crystallization. • Crystalline carbon nitride for solar-fuel generation and environmental purification was discussed. Semiconductor photocatalytic technology has become one of the most important means to solve the current energy shortage and environmental pollution. Compared with the traditional photocatalysts, graphite carbon nitride has a wider range of light-harvesting and more stable physical and chemical properties. However, traditional thermally induced polymerization of nitrogen-containing precursors produces the melon-based carbon nitride solids with an amorphous or semi-crystalline structure, resulting in low conductivity and moderate photocatalytic activity. Recently, crystalline carbon nitride has attracted more and more attention in improving photocatalytic performance. Some significant progress regarding crystalline carbon nitride for the preparation of solar-fuel and environmental purification has also been made. This review describes the recent advances in the design and synthesis of crystalline carbon nitride photocatalysts. A brief description of the unique physical and chemical properties of crystalline carbon nitride was given. Later, the synthetic and modification strategies are being introduced. Then, the photocatalytic application of crystalline carbon nitride was discussed, mainly including photocatalytic H 2 production, photocatalytic CO 2 reduction, and photocatalytic degradation of pollutants. Finally, the challenges and future directions of crystalline carbon nitride photocatalysts are briefly introduced. This review mainly summarizes the recent advances in the design and synthesis of crystalline carbon nitride. The modification strategies and the related energy and environmental applications of crystalline carbon nitride photocatalysts were discussed. [Display omitted] [ABSTRACT FROM AUTHOR]

Highly ordered Cu 2 O coated silicon nanowire arrays (SiNWAs) were fabricated as photocatalyst via depositing Cu nanoparticles on silver-assisted electroless-etched SiNWAs and subsequently annealing. The as-prepared samples have been characterized by scanning electron microscopy, X-ray diffraction and UV–VIS–NIR spectrophotometry. The photocatalytic properties of the Cu 2 O coated SiNWAs were investigated by degradation of Rhodamine B (RhB) under simulated solar light with a cut-off filter ( λ > 420 nm). The results indicated that H 2 O 2 could greatly improve the photocatalytic properties of Cu 2 O coated SiNWAs, and exhibited strong synergy effect between them. The hybrid nanowire arrays will be promising photocatalytic materials in the field of energy and environment. [ABSTRACT FROM AUTHOR]

Porous silica prepared by using an acrylic emulsion has been impregnated with bismuth ion resulting in Bi2SiO5 species containing surface. The as-prepared materials have been characterized by X-ray diffraction spectroscopy (XRD), X-ray photoelectron spectroscopy (XPS), UV–Vis diffuse reflectance spectroscopy (UV–Vis DRS), scanning electron microscopy (SEM), energy dispersive analysis of X-ray (EDAX), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR) and N2 adsorption/desorption techniques. EDAX analysis confirms the penetration of bismuth ions into the framework of silica to form Bi2SiO5, which is substantiated by XRD. The UV–Vis DRS shows that the catalysts are optically active and XPS confirms the inclusion of bismuth into the framework of silica. FTIR spectra illustrate the formation of Bi–O–Si linkages in the porous silica framework. SEM and TEM show the spherical morphology, whereas N2 adsorption/desorption study confirms the porosity of the prepared materials. The photocatalytic activity of the material is evaluated for the degradation of isoproturon herbicide and it is found that the material is active as compared to the commercial P-25 Degussa TiO2. [Copyright &y& Elsevier]