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Ca-doped BiFeO3 nanofibres have been fabricated by electrospinning method. Our results indicate that phase transition from space group R3c to C222 can be observed by the Ca doping. These BiFeO3 nanofibres show obvious room temperature ferromagnetic behaviors, and saturation magnetization can be enhanced with the Ca-doping concentration increasing, which could be correlated with the variation of the ratio of Fe2+/Fe3+ valence state. The BiFeO3 nanofibres show obvious photocatalytic performance and can be improved by the Ca-doping. [ABSTRACT FROM AUTHOR]

Abstract: To make better use of solar light, a new Bi2WO6/Cu1.8Se photocatalyst active to visible and near‐infrared light has been synthesized by a facile hydrothermal method. The composites were characterized by X‐ray diffractometry (XRD), scanning electron microscopy (SEM), UV‐vis diffuse reflectance spectroscopy (DRS), and photoluminescene (PL). The photocatalytic activities of Bi2WO6/Cu1.8Se are evaluated by degrading Congo red solution and hydrogen generation from water. It was found that the molar percentage of Cu1.8Se had great effects on the morphology and photocatalytic property of the Bi2WO6/Cu1.8Se heterojunctions, and the composite with suitable molar amount of Cu1.8Se exhibits much enhanced photocatalytic activity for Congo red degradation under visible and near‐infrared light irradiation and for hydrogen generation under visible light compared to Bi2WO6. The significant improvement photocatalytic activity of the composite could be attributed to its good light absorption, suitable band gap structure, and effective separation of photogenerated electron‐hole pairs of Bi2WO6/Cu1.8Se heterojunction. This work presents an efficient multifunction photocatalyst owning the activity both for water splitting under visible light and for organic contaminants decomposition under visible‐near‐infrared light. [ABSTRACT FROM AUTHOR]

In this work, a novel lignin-based carbon/ZnO (LC/ZnO) hybrid composite with excellent photocatalytic performance was prepared through a convenient and environment friendly method using alkali lignin (AL) as carbon source. The morphological, microstructure and optical properties of the as-prepared LC/ZnO hybrid composite was characterized with scanning electron microscope (SEM), X-ray diffraction (XRD), Raman and UV–vis. The resulting LC/ZnO hybrid is composed of highly dispersed ZnO nanoparticles embedded on a lignin-based carbon nanosheet, showing excellent photogenerated electrons and holes separation and migration efficiency. The photocatalytic activity of LC/ZnO was much higher than the pure ZnO. The LC/ZnO hybrid composite showed different photocatalytic mechanism for degradation of negative methyl orange (MO) and positive Rhodamine B (RhB). It showed that h + was the main photocatalytic active group during the degradation of MO, ·O 2 − and ·OH were the photocatalytic active groups during degradation of RhB. This reported photocatalyst with selective degradation of positive and negative organic dyes may have a great application prospect for photoelectric conversion and catalytic materials. Results of this work were of practical importance for high-valued utilization of lignin for carbon materials. [ABSTRACT FROM AUTHOR]

This work demonstrated a facile one-pot in-situ method to prepare lignin-based carbon/ZnO (LC/ZnO) nanocomposites by using lignin that was extracted from paper pulping waste liquor as the carbon source. The morphological, physical and optical properties of the prepared LC/ZnO nanocomposites was characterized with Scanning electron microscope (SEM), Transmission electron microscopy (TEM), Thermal-gravimetric analysis (TGA), Raman, X-ray diffraction (XRD) and Brunauer-Emmett-Teller (BET) analyses. The resulting LC/ZnO is composed of highly dispersed ZnO nanoparticles embedded on a lignin-based carbon nanosheet. The typical D and G bonds of carbon materials obviously appeared. The TGA shows that the LC contents could be controlled. The BET surface area of the LC/ZnO was much larger than the BET surface area of the pure ZnO. The prepared LC/ZnO nanocomposites exhibited excellent photocatalytic performance for the degradation of organic dyes. LC/ZnO that contained ∼6.38% lignin-based carbon exhibited an excellent photo-degradation efficiency of methyl orange as high as 98.9% under sunlight irradiation for 30 min, superior to the performance of pure ZnO and other reported ZnO/GRs. The improved photocatalytic performance was attributed to a homogeneous structure and stronger absorption ability for organic dyes. The mechanism exploration experiment showed that h + was the main active specie. Meanwhile, the photocatalytic electron transfer mechanism was also investigated. In addition, this work demonstrates a green and valuable pathway for the high-value-added utilization of lignin. [ABSTRACT FROM AUTHOR]

[Display omitted] • Cu 3 Pd 1 /SN exhibits a high performance for semihydrogenation of phenylacetylene. • Cu 3 Pd 1 /SN could activate phenylacetylene via C≡C → Nb π-bonded coordination. • The photogenerated electrons facilitate the production of active H. Bimetallic alloy of CuPd nanoclusters decorated SnNb 2 O 6 nanosheet (CuPd/SN) as a multifunctional photocatalyst has been constructed successfully. Compared with SN, CuPd/SN achieves an excellent performance for semihydrogenation of phenylacetylene under visible light irradiation. Especially, CuPd/SN with the Cu:Pd molar ratio of 3:1 exhibits the highest catalytic conversion efficiency for phenylacetylene (99.6%) with high selectivity of phenylethylene (99.4%). In situ FTIR result reveals that SN could activate phenylacetylene via a C≡C → Nb π-bonded coordination which improves the selectivity of phenylethylene. Experiment results indicate that atom Pd in alloy is responsible for dissociation H 2 , while Cu represses the overhydrogenation. Electrochemical measurements suggest that CuPd alloy on SN surface could greatly minimize the recombination of photogenerated electron − hole pairs. The separated electrons further facilitate the production of active H. Hydrogen spillover would transfer active H to Nb site for phenylacetylene semihydrogenation. Finally, a synergetic catalytic mechanism is deeply discussed at molecule scale. This work would provide a deep insight for designing a multifunctional photocatalyst. [ABSTRACT FROM AUTHOR]

BiFeO3 nanofibers doped with divalent barium have been fabricated using electrospinning technique. Phase transition from space group R3c to C222 can be observed by the Ba doping. Our results indicate that these BiFeO3 nanofibers show obvious room temperature ferromagnetic behaviors, which can be enhanced remarkably with the increment of Ba doping. Microstructure and composition analysis indicates that barium effectively affected the magnetism after doping content was more than 5% and optical properties. [ABSTRACT FROM AUTHOR]

Highlights: [•] Plamonic Ag@AgCl was intercalated in the layered space of K4Nb6O17. [•] Ag@AgCl greatly increased visible light absorption for K4Nb6O17. [•] The plamonic photocatalysts exhibited enhanced activity for the degradation of RhB. [Copyright &y& Elsevier]

Highlights: [•] Plasmonic Ag@AgBr was intercalated in the layered space of K4Nb6O17. [•] Ag@AgBr greatly increased visible light absorption for K4Nb6O17. [•] The plasmonic photocatalysts exhibited enhanced activity for the degradation of RhB. [ABSTRACT FROM AUTHOR]

Abstract: In this study, a novel plasmonic photocatalyst, Ag@AgI intercalated layered niobate, was synthesized via a microwave-assisted ion-exchange method. The composite materials prepared were characterized by using X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), transmission electron microscopy (TEM), X-ray fluorescence spectrometry (XRF), Brunauer–Emmett–Teller (BET) and ultraviolet–visible diffuse reflection spectra (UV–vis). The as-prepared plasmonic photocatalyst exhibited an enhanced and stable photocatalytic performance for the degradation of Rhodamine B (RhB) and up to 83% of RhB was degraded in 40min under visible light irradiation. The mechanism of separation of the photo-generated electrons and holes at the K4Nb6O17/Ag@AgI composite was discussed. [Copyright &y& Elsevier]

In the synthesis of organic hybrid metal chalcogenides, piperazine (pip) has been widely applied as a template or charge-balancing agent in the structure assembly, but application of piperazine as a solvent to synthesize organic hybrid metal chalcogenides has not been reported. In this work, two new two-dimensional layered organic hybrid silver chalcogenidoantimonates, namely [pipH 2 ] 0.5 [Ag 2 SbS 3 ] (1), [pipH 2 ] 0.5 [Ag 2 SbSe 3 ] (2), have been synthesized by using piperazine as reaction medium. Both compounds possess the similar honeycombed anionic bilayers, and the biprotonated piperazine cations are resided between the bilayers. Thermal stabilities and optical properties of compounds 1 and 2 have been studied. Moreover, compounds 1 and 2 exhibited excellent photocatalytic activities for reducing aqueous Cr(VI) under visible light irradiation. [Display omitted] • Two new silver chalcogenidoantimonates were prepared by using piperazine as reaction medium. • Both compounds showed excellent photocatalytic activity for reducing Cr(VI) under visible light irradiation. • The effects of pH value and initial concentration on the catalytic performance were studied. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Nitroanilines are important building blocks in pharmaceuticals, materials and dyes. Nitration methods for anilines under mild conditions are highly desired. Herein, we report a photochemical method for the nitration of anilines bearing various protecting groups by 5‐methyl‐1,4‐dinitroimidazole as a new type of nitro source. This method is light‐controlled and proceeds under mild reaction conditions with high efficiency. Fmoc‐, Ts‐ and alkyl‐protected anilines are all well nitrated with good functional group tolerance. [ABSTRACT FROM AUTHOR]

ZnIn2S4 is a promising candidate for photocatalysis. However, it is still facing great challenge to improve its photocatalytic activity through rationally regulating its microstructures. Herein, ZnIn2S4 micro-flowers with different self-assembly microstructures were synthesized by solvent induced through one-step hydrothermal method, and were used as catalytic dehydrogenation of 1,2,3,4-tetrahydroisoquinoline to 3,4-dihydroisoquinolines. Different solvents have great effects on the microstructure of ZnIn2S4. The surface of ZIS-H2O petals is relatively smooth, and the petals of ZIS-EtOH are micro-discoid and relatively rough. The microstructure of ZIS-EG is the smallest and consists of countless irregular thin nanosheet. The results show that ZIS-EG assembled with ethylene glycol as solvent has the best photocatalytic activity in the catalytic dehydrogenation. The maximum conversion of 98% as well as the selectivity of 99% of 3,4-dihydroisoquinolines was accomplished under air condition with 7-h visible-light irradiation. The excellent photocatalytic activity of ZIS-EG benefits from its excellent absorption of visible light as well as the separation efficiency of photogenerated carriers. Therefore, this work has provided an effectively method to accelerate the photocatalytic activity through solvent-induced controlling microstructures. A series of ZnIn2S4 photocatalysts with different microscopic morphologies were synthesized, and were used as catalytic dehydrogenation of 1, 2, 3, 4-tetrahydroisoquinoline to 3, 4-dihydroisoquinolines. The results show that ZnIn2S4 synthesized in ethylene glycol solvent has the best photocatalytic dehydrogenation activity. [ABSTRACT FROM AUTHOR]

Photocatalytic H 2 production from methanol is sustainable, yet challenges remain in avoiding carbon-containing gaseous by-products. Titanium silicalite-1 (TS-1) zeolite possesses attractive photocatalytic performance, but lack of modification strategies due to its microporous framework. Herein, we developed a pre-anchoring strategy to confine ultra-small Pt clusters inside TS-1 with ultra-low loading (0.2 mol%), in which Pt were anchored in Ti−OH nests by electronic metal-support interaction (EMSI). The optimal catalyst achieved a remarkable H 2 generation rate of 63.2 mmol g–1 h–1 in CH 3 OH solutions, along with the production of high-value chemical HCHO as the oxidation product with 96.9% selectivity. Investigations reveal that the EMSI between Pt and Ti facilitated the selective decomposition of CH 3 OH to H 2 and HCHO, leading to a nearly zero-carbon-emission process. Accordingly, we propose a light-driven carbon-negative "CO 2 →CH 3 OH→H 2 " route, coupling CO 2 utilization and green H 2 production with CH 3 OH as the intermediate, therefore offering a new perspective for "liquid sunshine". [Display omitted] • Pt clusters were successfully encapsulated inside TS-1 by a pre-anchoring method. • The optimal catalyst achieved a remarkable photocatalytic H 2 generation activity. • HCHO is the main oxidation product with nearly 100% selectivity. • The strong EMSI between Pt and Ti facilitated CH 3 OH decomposition to H 2 and HCHO. • A potential light-driven carbon-negative "CO 2 →CH 3 OH→H 2 " route was proposed. [ABSTRACT FROM AUTHOR]

• The Fe-doped TiO 2 S-scheme anatase/rutile homojunction (F-T-A/R) was synthesized by a typical solvothermal-annealing method. • The optimized F-T-A/R photocatalyst (A/R = 98:2, Fe-2 wt%) exhibits an unprecedented NH 3 generation rate of 358 μmol gcat-1h−1. • The charge transfer mechanism of S-scheme homojunction and NH 3 production path were investigated. • The synergistic effect of S-scheme homojunction and Fe doping improved the photocatalytic nitrogen fixation. The presence of efficient catalytic active sites and an ample supply of electrons are the two indispensable factors for achieving photocatalytic nitrogen fixation. Herein, the Fe-doped TiO 2 S-scheme anatase/rutile homojunction (F-T-A/R) was synthesized as a brilliant photocatalyst for photocatalytic nitrogen fixation from N 2 to NH 3 under ambient atmosphere. The optimized F-T-A/R photocatalyst (A/R = 98:2, Fe-2 wt%) exhibits an unprecedented NH 3 generation rate of 358 μmol g cat -1h−1 in water solvent and under simulated solar light irradiation. Experimental and theoretical studies reveal that the constructed S-scheme homojunction in F-T-A/R is conducive to fluent charge separation and adequate supply of electrons on rutile with higher nitrogen fixing activity, while the tuned local electronic structure of oxygen vacancy with Fe doping is engineered to strengthen active sites, synergistically enhancing the photocatalytic nitrogen fixation. [ABSTRACT FROM AUTHOR]

The application of ZnO nanoparticles as photocatalyst is significantly hampered by limited absorption range for solar spectrum, fast recombination of photogenerated carriers and poor recyclability. The modification with carbon structures has attracted attention as their advantageous performance in photocatalysis. Herein, we first report a lignin-derived flower-like carbon (LFC), which is used to modify ZnO. The resulting composite (ZnO/LFC) is composed of ZnO nanoparticles (∼10 nm) embedded on a flower-like carbon consisting of two-dimensional corrugated nanosheets. Especially, LFC exhibits stable three-dimensional structure and rich oxygen-containing functional groups. So ZnO can be uniformly anchored on the LFC. Composite presents an extended optical absorption and enhanced separation of photogenerated carriers due to the interface electronic interaction between ZnO and LFC. The hierarchical flower-like structure facilitates fast substance transfer and high light-harvesting efficiency. Therefore, ZnO/LFC presented an excellent photocatalytic activity toward degradation of sulfamethazine and hydrogen evolution, which were about 3.0 and 2.1 times that of pure ZnO, respectively. Moreover, the recyclability of composite photocatalyst was also significantly better than pure ZnO. This work not only provides a facile, low-cost and scalable strategy to promote practical application of photocatalyst but also opens new path toward the high-value utilization of industrial lignin. Image 1 • Lignin-based carbon with flower-like structure was first prepared. • Flower-like carbon was obtained with a facile EISA and carbonization process. • ZnO nanoparticles were anchored uniformly onto LFC by in-situ growth method. • LFC extended optical absorption and enhanced separation of charge carriers of ZnO. • ZnO/LFC presented excellent photocatalytic efficiency and recyclability. [ABSTRACT FROM AUTHOR]

Organic-inorganic hybrid nano-material has a significant potential for enhancing the charge separation efficiency of photocatalyst. However, it remains an important issue to controllable synthesis new hybrid system with unique structure and earth-abundant materials for boosting photocatalytic hydrogen revolution. We report a facile one-step hydrothermal strategy to fabricate a novel Titania/β-cyclodextrin (TiO 2 /β-CD) organic-inorganic hybrid nano-material with an alveolate structure. In this hybrid system, β-CD not only played a critical role in alveolate structure formation, but also served as a bridge connecting target molecular and active sites on the TiO 2 surface to facilitate the separation and transfer of the photoexcited electrons with prolonged lifetime. As a result, this alveolate TiO 2 /β-CD composite exhibited outstanding photocatalytic activity and a H 2 evolution rate of 725 μmol/g·h was achieved over TiO 2 /β-CD which was 14 times of bare TiO 2 under simulated sunlight. This work paves a way for controllable synthesis of novel organic-inorganic hybrid nano-material with distinct structure for efficient photocatalysis. Image 1 • A novel alveolate organic-inorganic hybrid has been successfully prepared. • The hybrid composite exhibited outstanding photocatalytic activity. • The H 2 evolution rate of TiO 2 /β-CD has a good durability. • This work paves a way for controllable synthesis of organic-inorganic TiO 2. • Limited reports on the photocatalytic water splitting of the TiO 2 /β-CD. [ABSTRACT FROM AUTHOR]

Abstract Cuprous oxide has important applications from photovoltaic devices to photocatalysis and nitrogen-doping can improve the p-type conductivity of cuprous oxide. Here, phase-pure cuprous oxide thin films are prepared by sputtering a copper target in the atmosphere of Ar, O 2 and N 2 with the sputtering pressure varying from 0.6 Pa–3.0 Pa. The samples deposited at 0.6 Pa is also annealed in the flow of Ar or Ar plus N 2. The results show that sputtering pressure below 1.0 Pa results in higher deposition rate and more nitrogen incorporation into cuprous oxide while sputtering pressure of 3.0 Pa leads to lower deposition rate and no nitrogen doping though the gas flow rates are the same. In nitrogen-doped Cu 2 O, nitrogen exists as β-N (atomic nitrogen), α-N 2 (-N=N-) and γ-N 2 (N N). Annealing completely removes β-N and partially turns α-N 2 into γ-N 2. Nitrogen-doped cuprous oxide has smaller resistivity and larger hole density than undoped samples. The longest time for the absorbed nitrogen molecules to stay on the copper position is estimated to be 8.45 × 10−7 s. Annealing has little effect on the electrical and optical properties of nitrogen-doped cuprous oxide though it induces a weak decomposition. Highlights • The nitrogen content in Cu 2 O was controlled by varying the sputtering pressure. • Lower sputtering pressure results in higher deposition rate. • Lower sputtering pressure favors the incorporation of nitrogen into Cu 2 O. • Lowering sputtering pressure increases the hole density. • Annealing at 400 °C results in little electrical and optical change. [ABSTRACT FROM AUTHOR]

Graphical abstract The Lewis acid sites (Ti) in TNS would selectively adsorb OH in cinnamyl alcohol forming surface C O···Ti O coordination species. Under visible light irradiation, interface charge transfer occurs from C O to Ti O , resulting in the activation of cinnamyl alcohol and the charge enrichment in Ti atoms of TiO 6. The molecule O 2 would be adsorbed on the electron enriched Ti atoms and reduced to O 2 − for the oxidation of alcohol. Due to the hybrid electronic states of Cu-Cu 2 O, the interface electronic transfer kinetics are tuned to inhibit the intramolecular hydrogen transfer for dominating the selectivity towards cinnamaldehyde. The synergistic effect of surface coordination-activation-photocatalysis enables an efficient and green synthesis. Highlights • The coordination of hydroxyl in alcohol with surface Lewis acid sites of H 1.4 Ti 1.65 O 4 ·H 2 O nanosheets. • Directional interface charges transfer from alcohol to nanosheet occur via surface coordination species. • The hybrid electronic states of Cu-Cu 2 O tune interface charges transfer kinetics. • Synergistic surface coordination-activation-photocatalysis for precies synthesis. Abstract A multifunctional photocatalyst is constructed based on Cu-Cu 2 O hybrid and monolayer H 1.4 Ti 1.65 O 4 ·H 2 O nanosheets via an in situ photo-deposition process (Cu-Cu 2 O/TNS). The prepared sample enables the oxidation of cinnamyl alcohol to cinnamaldehyde with over 95% of selectivity under visible light irradiation using molecule O 2 as the oxidant. In situ FTIR spectra suggest that the Lewis acid sites in TNS would selectively adsorbed the hydroxyl of cinnamyl alcohol forming surface C O∙∙∙Ti O coordination species. UV-DRS spectra reveal that light adsorption of TNS can be extended to visible light region due to the interface charges transfer from C OH to Ti O via the surface coordination, resulting in the activation of OH in alcohol. In situ ESR further indicates that directional interface charge transfer induces the charge enrichment in Ti atoms of TiO 6 , facilitating O 2 adsorption. XAFS results reveal that the hybrid electronic states of Cu-Cu 2 O efficiently improve the interface electronic transfer kinetics to inhibit the intramolecular hydrogen transfer for dominating the selectivity towards cinnamaldehyde. This work highlights the synergistic effect of surface coordination-activation-photocatalysis for selective photosynthesis of fine chemicals. [ABSTRACT FROM AUTHOR]

In this work, pompon-like structured g-C3N4/ZnO composite photocatalyst was fabricated by a two-step method and characterized through different characterization tools to determine the photophysical properties. It is discovered that the synthesized pompon-like g-C3N4/ZnO photocatalyst is composed of flake g-C3N4 coated on the pompon surface of ZnO to form a heterojunction structure. In the composite photocatalyst, the pompon ZnO has large surface area (41.81 m2/g) which can provide more reactive sites for composite catalysts, the g-C3N4 can absorb the visible light which can effectively expand the absorption range of the composite, and the heterostructure formed between g-C3N4 and pompon ZnO can effectively reduce the coincidence efficiency of photo-generated carriers. The photocatalytic performance of pompon-like g-C3N4/ZnO photocatalyst was evaluated by photocatalytic degradation of rhodamine B (RhB) organic dyes under simulated solar light irradiation and the optimum doping amount of g-C3N4 is 10%. The stability of the composite photocatalyst was tested by five runs of RhB photodegradation under simulated visible light. [ABSTRACT FROM AUTHOR]

To improve optoelectronic properties of bismuth oxyhalides, hybrid BiOX photocatalytic materials have draw a great attention, because of the separation of photogenerated electron-hole pairs. The band offset and band alignments are considered as the key parameters to elaborate carrier transport properties in heterojunction. In this paper, to determine the band alignment of BiOCl and ZnO heterostructure, BiOCl/ZnO core shell nanosheets with different thickness of shell layer were synthesized. The valence band offset (VBO or ΔEV) of BiOCl/ZnO heterostructure was determined using X-ray Photoelectron Spectroscopy measurements. The ΔEV value of 0.294 ± 0.10 eV was calculated by using the Zn 2p3/2, Bi 4f5/2 binding energies as references. Taking the band gaps of 3.37 eV and 3.4 eV for ZnO and BiOCl samples into consideration, respectively, we obtained the type-II band alignment of BiOCl/ZnO heterostructure with a conduction band offset (CBO or ΔEc) of 0.324 ± 0.10 eV. [ABSTRACT FROM AUTHOR]

Purpose The aim of this paper is to synthesize graphene-modified titanium dioxide (GR-TiO2) nanorod arrays nanocomposite films, so that these can enhance the photocatalytic properties of titanium dioxide and overcome the problem of difficult separation and recovery of photocatalysts.Design/methodology/approach The GR-TiO2 nanocomposite films were synthesized via hydrothermal method and spin-coating. The obtained samples were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), ultraviolet–visible (UV-Vis) diffuse reflectance spectrum and Raman spectrum. The photocatalytic performance of the GR-TiO2 nanocomposite films for degrading Rhodamin B under ultraviolet (UV) was studied by a UV-Vis spectrophotometer. The photocatalytic enhancement mechanism of graphene was studied by photoelectrochemical analysis.Findings The introduction of graphene expanded the range of the optical response of TiO2 nanorod arrays, improving the separation efficiency of the photogenerated electron-hole pairs, and thus dramatically increasing its photocatalytic performance.Research limitations/implications A simple and novel way for synthesizing GR-TiO2 nanocomposite films has enhanced the photocatalytic performance of TiO2.Originality/value The photocatalyst synthesized is easy to separate and recycle in the process of photocatalytic reaction, so it is possible to achieve industrialization. [ABSTRACT FROM AUTHOR]

Solar driven catalysis by semiconductors is considered as a promising route to mitigate environmental problems caused by the combustion of fossil fuels and water pollution. Surface plasmon resonance (SPR) has offered a new opportunity to overcome the limited efficiency of photocatalysts. Herein we report that the SPR-mediated visible-light-responsive photocatalyst, 0.5 wt.% Au/SO 4 2− –TiO 2 , can achieve over 99% conversion of pollutants (thiophene, thiol, rhodamine B, and phenol) during photocatalytic oxidation with oxygen or air as oxidant under visible light irradiation. The considerable enhancement of photocatalytic activity can be attributed to the synergistic effect of Au SPR and Lewis acidic SO 4 2− –TiO 2 which are beneficial for the efficient separation and transfer of the photo-generated electrons and holes. Such a strategy would be important to the design and preparation of highly photocatalytic active semiconductor catalysts. [ABSTRACT FROM AUTHOR]

A novel ultrasensitive label-free immunosensor based on BiOBr/Ag 2 S composite with high visible-light photoelectrochemical activity was prepared for the detection of insulin. After BiOBr was modified by thioglycolic acid, Ag 2 S nanoparticles were grown in-situ on the surface of BiOBr hierarchical microspheres to first form novel BiOBr/Ag 2 S composite. When ascorbic acid (AA) was used as an efficient electron donor for scavenging photo-generated holes, BiOBr/Ag 2 S composite material showed excellent photoelectrochemical activity. In order to immobilize insulin antibody, adhesive polydopamine (PDA) film formed by self-polymerization of dopamine was fabricated onto BiOBr/Ag 2 S modified electrode. Moreover, PDA film could further enhance the visible light absorption of BiOBr/Ag 2 S. When the solutions of 0.08 mol L −1 AgNO 3 and 0.1 mol L −1 AA were selected respectively during fabrication and detection process of this sensor, the best photocurrent singles were obtained. Under the optimum experimental condition, the specific binding between insulin and antibody resulted in a decrease in photocurrent intensity and the intensity decreased linearly with the logarithm of insulin concentration in the range of 0.001–20 ng mL −1 with a detection limit of 0.2 pg mL −1 . The photoelectrochemical sensor ITO/BiOBr/Ag 2 S/PDA/anti-Insulin/BSA/Insulin revealed facile preparation, high sensitivity, and acceptable reproducibility, which may have practical applications in the biosensor, clinical diagnosis of cancers, photocatalysis, and other related fields. [ABSTRACT FROM AUTHOR]

Bi1- xSm xFe1- yMn yO3 ( BSFMO, x = 0.0, 0.05; y = 0.0, 0.05, 0.10, 0.15, 0.20, 0.25) nanoparticles were synthesized by using double solvent sol-gel method. Photocatalytic activity was investigated under UV and visible-light illumination. The structural, morphological, and optical properties were analyzed by X-ray diffraction, scanning electron microscopy, and UV-vis spectroscopy respectively. The crystallite size of BiFeO3 ( BFO) decreases from (57.3-17.2 nm) with the increase in Sm and Mn-doping concentration. The surface morphology shows that the pure and Sm-doped BFO nanoparticles are irregular in shape but changes to spherical shape after Mn-doping up to 25%. The band-gap engineering of BFO nanoparticles is achieved by co-doping of Sm and Mn. The band-gap of BFO could be tuned successfully from 2.08-1.45 eV, which may be due to the distortion induced in Fe-O octahedron and the rearrangement of molecular orbitals. These results give rise to enhanced photocatalytic activity by degradation of organic dyes ( MB, CR, and MV) under the visible-light illumination. [ABSTRACT FROM AUTHOR]

We report a simple mechanochemical ball milling method for synthesizing monodisperse CuS quantum dots (QDs) with sizes as small as sub-5 nm. The products were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS) and UV–vis spectroscopy. The CuS QDs exhibited excellent visible-light-driven photocatalytic activity and stability for degradation of Rodanmine B aqueous solution as Fenton-like reagents. Our study opens the opportunity to low-cost and facile synthesis of QDs in large scale for future industrial applications. [ABSTRACT FROM AUTHOR]

• Au@TiO 2 /Bi 2 WO 6 was synthesized by reverse micelle sol–gel method plus hydrothermal process. • Remarkable photocatalytic performance for degradation of antibiotics was achieved. • The Z-scheme charge transfer mechanism for Au@TiO 2 /Bi 2 WO 6 was verified. • The nanocomposite photocatalyst exhibited superior reusability. Semiconductor photocatalysis can be regarded as one of effective strategies to overcome the great challenges encountered with conventional technologies for environmental remediation. In this research, Z-scheme heterostructure composed of core–shell Au@TiO 2 nanoparticles and flower-like Bi 2 WO 6 nanosheets has been successfully prepared through the reverse micelle sol–gel method followed by a hydrothermal process. The structural characteristics, chemical compositions and photoelectrochemical properties of this ternary composite photocatalyst (Au@TiO 2 /Bi 2 WO 6) were further investigated in detail. Benefitted from the synergy of the heterojunction construction and metallic surface plasmon resonance effect, the Au@TiO 2 /Bi 2 WO 6 with an optimal mass ratio of Au@TiO 2 to Bi 2 WO 6 exhibited the significantly enhanced photocatalytic activity for degradation of antibiotics under visible-light irradiation, in which the degradation efficiency of sulfamethoxazole (SMX) and tetracycline hydrochloride (TC) could be up to 96.9% and 95.0% within 75 min, respectively. The reaction rate constant for SMX and TC degradation was calculated to be around 0.0425 min−1 and 0.0314 min−1, which has 7.2 times and 1.9 times enhancement compared with single Bi 2 WO 6 , respectively. In addition, the cyclic stability and photocatalytic mechanism of Au@TiO 2 /Bi 2 WO 6 were further verified. Our primary results provide a feasible strategy to develop core–shell heterostructured photocatalysts with superior performance for the efficient removal of low-concentration antibiotics in water. [ABSTRACT FROM AUTHOR]

In this work, Bi 2 S 3 /SnS 2 heterojunction photocatalysts were prepared by combining a hydrothermal technique and a facile in situ growth method. The nanocomposites were characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, inductively coupled plasma spectroscopy, X-ray photoelectron spectroscopy, UV–Vis diffusion reflectance spectroscopy and room-temperature photoluminescence spectra. Their photocatalytic performances were evaluated by degrading methyl orange (MO) in aqueous solution (50 mg/L) under visible light (λ > 420 nm) irradiation. It was found that when the mass percentage of Bi 2 S 3 in Bi 2 S 3 /SnS 2 was 7.95 wt%, the as-prepared Bi 2 S 3 /SnS 2 nanocomposite showed the best photocatalytic activity for the degradation of MO. The highly improved performance of the Bi 2 S 3 /SnS 2 nanocomposite was mainly ascribed to the efficient charge separation. [ABSTRACT FROM AUTHOR]

In this study, porous g-C 3 N 4 with structural defects of oxygen atom and cyano group (COCN) prepared by thermal polymerization of directly calcinating the mixture of urea and ascorbic acid, is firstly applied in the H 2 O 2 fuel cell. By employing a nickel mesh coated with COCN as the photoanode and iron phthalocyanine (FeIIPc) mixed with g-C 3 N 4 on carbon paper as the cathode, this COCN-based cell exhibits a maximum power density of 0.298 mW·cm−2 in the water solution including 0.1 M HCl under AM 1.5G solar light at air atmosphere, which has an approximate 5.0 times enhancement compared with that of pristine g–C 3 N 4 –based one. The corresponding solar-to-electricity conversion efficiency (SECE) of above cell is estimated to be 0.248%. In addition, the photocatalytically produced H 2 O 2 (chemical energy) is stored in water with the electrodes disconnected under light irradiation for 3 h, and then is directly used as the fuel in an H 2 O 2 fuel cell by connecting the electrodes in the dark, yielding a specific capacitance of 5900 mF·cm−2. After 6 h of cell operation, the retention rate of specific capacitance is still as high as 76.9%. The primary results provide a facile strategy to introduce structural defects in g-C 3 N 4 for boosting H 2 O 2 fuel cell performance. [Display omitted] • Porous g-C 3 N 4 with structural defects (COCN) is applied in the H 2 O 2 fuel cell. • The structural defects in COCN facilitate the photocatalytic H 2 O 2 generation. • The COCN as the photoanode produces 0.036 M H 2 O 2 under light irradiation for 3 h. • The COCN-based cell converts solar energy to H 2 O 2 fuel for generating electricity. • The specific capacitance keeps 76.9% of initial value after 6 h of cell operation. [ABSTRACT FROM AUTHOR]

The surface plasmon resonance (SPR) effect of noble nanometals can be utilized to effectively improve the catalytic performance of semiconductor photocatalysts. In this work, a novel composite photocatalyst of BiOBr microspheres simultaneously decorated by Ag and Bi dual nanoparticles (NPs) has been successfully synthesized by the hydrothermal method plus one-step reduction method. And the morphology, structure, chemical composition and photoelectrical properties of this composite photocatalyst (Ag/Bi–BiOBr) were further characterized. Due to the SPR effect of Ag and Bi dual NPs, Ag/Bi–BiOBr showed the high light absorption with narrow band gap, as well as fast charge separation via metal-semiconductor heterojunction so as to realize an efficient degradation of ibuprofen (IBP) under simulated solar irradiation. Through the further optimization of the loading amounts of Ag and Bi dual NPs, the excellent photocatalytic activity in the Ag/Bi–BiOBr has been achieved that 92.3% of IBP was removed within 60 min, which is among the best results reported so far for IBP degradation via photocatalysis. A facile preparation strategy of novel highly-active composite photocatalyst of BiOBr microspheres decorated by Ag and Bi dual nanoparticles has been proposed for efficient degradation of ibuprofen. • A simple one-step reduction strategy was proposed to prepare Ag/Bi dual nanoparticles-decorated BiOBr (Ag/Bi-BiOBr). • Bi nanoparticles were directly reduced from BiOBr without additional Bi precursors. • Ag and Bi nanoparticles increased the light absorbance and decreased the charge recombination. • The Ag/Bi-BiOBr showed efficient and stable photocatalytic activity on ibuprofen degradation. • The holes (h+) and electrons (e−) were the uppermost active species for ibuprofen degradation. [ABSTRACT FROM AUTHOR]

Semiconducting photocatalysts composited with noble nanometals can be regarded as one of effective strategies to enhance the photocatalytic activity, attributed to a synergy of heterojuction formation and surface plasmon resonance effect. However, the dosage of nanometal in the composite for achieving an optimal performance is commonly larger than 10 wt%, causing high cost in raw materials. In this work, a composite photocatalyst of flower-like bismuth tungstate (Bi 2 WO 6) nanosheets decorated by low-dosage silver nanoparticles (Ag NPs) with the excellent photocatalytic activity for sulfamethoxazole (SMX) degradation was prepared. Further, the morphological and structural characteristics, chemical compositions, and photoelectrical properties of this composite photocatalyst (Ag/Bi 2 WO 6) were investigated. Different loading amounts of Ag NPs (1, 3 and 5 wt%) in Ag/Bi 2 WO 6 were modulated, and when the dosage of Ag NPs was controlled to be only 3 wt%, the composite photocatalyst exhibited the most efficient degradation that 95.04% of SMX was removed within 60 min under visible light irradiation, which has around 3 times enhancement compared to single Bi 2 WO 6. The sacrificial agent experiment indicated that •O2− and •OH are the main active substances in the photocatalytic degradation of SMX. And the cyclic experiment further confirmed the Ag/Bi 2 WO 6 composite with high stability and reusability. The photocatalytic mechanism was verifiably proposed that the enhanced degradation performance was derived from more effective light absorption and photogenerated charge separation by loading Ag NPs onto Bi 2 WO 6. Our primary results provide a basic platform for exploring the high catalytic-activity photocatalysts with low-dosage noble nanometals. [ABSTRACT FROM AUTHOR]

• A type II heterojunction was formed between surface of ZnIn 2 S 4 and ZnO. • Efficient oxidative coupling of benzylamine was realized under visible light. • No extra oxygen atmosphere was required. A series of Zn x In y S z was synthesized by hydrothermal method, and the corresponding Zn x In y S z @ZnO composites with the internal type II heterojunctions were prepared by solvent assisted interface. It could be observed in SEM and TEM images of ZnIn 2 S 4 @ZnO that ZnIn 2 S 4 present a petal-like sphere composed ofnanosheets with nano-fragments of ZnO attached on its surface. The results offluorescence spectra and electrochemical impedance spectroscopy indicated that theformation of type II heterojunctions within ZnIn 2 S 4 @ZnO composites significantly promotedthe separation of photocarriers. Therefore, ZnIn 2 S 4 @ZnO delivered excellent catalyticperformance for oxidative coupling of benzylamine. Under visible-light irradiation of 2 h, the conversion of benzylamine is as high as 96%, and the catalytic performance is still very steady after several cycles. It has not been reported that such a high conversion can be achieved in such a short period of time. Another advantage is that the coupling reaction does not require additional oxygen atmosphere and can be carried out in air condition, endowing this process with the feature of easier to be operated. This work provids an effective method for oxidative coupling of benzylamine through environmentally friendly way.This work provided an effective method for coupling of benzylamine environmentally friendly way. Zn x In y S z and Zn x In y S z @ZnO composite photocatalysts were synthesized by hydrothermal and solvent assisted interface reaction for the oxidative coupling of benzylamine. Of all the photocatalysts ZnIn 2 S 4 @ZnO showed the most excellent photocatalytic activity for the coupling. It found ZnIn 2 S 4 @ZnO formed type II heterojunction and realized the efficient separation of electrons and holes in the catalytic process. The conversion of benzylamine reached 96% only after 2 h of visible light irradiation. This reaction does not require additional oxygen atmosphere and can be carried out in air condition. [Display omitted] [ABSTRACT FROM AUTHOR]

Highlights: [•] CdS urchins decorated with α-Fe2O3 or Fe3O4 nanoparticles were synthesized. [•] The heterostructures were used as visible light-driven photocatalysts. [•] Both the heterostructures showed the enhanced photocatalytic cycled activities. [Copyright &y& Elsevier]

[Display omitted] • The low-cost Cu 2 O/g-C 3 N 4 heterojunction is constructed by simple hydrothermal method. • Cu 2 O/g-C 3 N 4 exhibited synergistic effects of thermalcatalysis and photocatalysis. • The overpotential reduce by 0.34 V in ILs than KHCO 3 electrolyte. • We provided strategy of CO 2 reduction to ethanol assisted by ILs under thermal field. Photocatalytic CO 2 reduction is a potential way to address simultaneously environmental pollution and energy shortage. However, the difficulties of CO 2 activation and C C coupling lead to quite low conversion efficiency of CO 2 to C2 products. In this study, we constructed Cu 2 O/g-C 3 N 4 heterojunction for photocatalytic CO 2 reduction to ethanol by coupling thermal field and ionic liquids (ILs). The ethanol rate reached 0.71 mmol·g−1·h−1 over Cu 2 O/g-C 3 N 4 under photothermalcatalysis, which is 1.89 times that of photocatalysis and 7.05 times that of thermal catalysis. The temperature enhanced thermal motion of the radical, which promotes the formation of ethanol through the ·CH 3 dimerization. The 1-aminopropyl-3-methylimidazolium bromide ILs shows superior CO 2 reduction performance with a high current density (21.3 mA·cm−2) than KHCO 3 electrolyte (12.8 mA·cm−2). The overpotential is reduced by 0.34 V, which accelerates CO 2 reduction by reducing polarization. It is found that the ILs played a key role in suppressing H 2 O reduction and increasing ethanol yield in this photothermalcatalytic strategy. [ABSTRACT FROM AUTHOR]

Abstract: Reduced graphene oxide/cadmium sulfide (RGO/CdS) hybrid material was synthesized by a one-step solvothermal method, wherein graphene oxide (GO) was a supporting material on which CdS nanoparticles were distributed homogeneously, and cadmium acetate (Cd(Ac)2·2H2O) was used as the CdS precursor. The supporting material RGO for CdS nanoparticles effectively enhanced their photocatalytic activities for the photodegradation of methylene blue in the aqueous solution. The optimum weight ratio of the GO to CdS in the hybrid material was 5.0%, which exhibited an excellent photodegradation efficiency (94%) and a better removal efficiency of total organic carbon (TOC) (57%), about 2.5 times and 5.1 times higher than that of pure CdS nanoparticles, respectively, under visible light (VL) irradiation. This improved photodegradation efficiency could be attributed to the increased adsorbability for methylene blue molecules, light absorption levels located in visible region, high charge transfer and separation ability, due to the introduction of a two-dimensional RGO network. [Copyright &y& Elsevier]

• A fascinating three-dimensional double-walled framework channels was obtained. • Compound 1 exhibited a stable activity for methyl violet degradation after four consecutive usages. • The plausible mechanism was investigated in detail. A new Dy(III)-based metal–organic framework (MOF) having formula [Dy 2 (La) 2 (ox)(H 2 O) 4 •4H 2 O] n (1) has been synthesized under hydrothermal condition using 5-(1H-1,2,4-triazol-1-yl)isophthalic acid (H 2 La), oxalic acid (H 2 ox) and DyCl 3. The single crystal X-ray crystallography revealed that the MOF 1 shows 3D double-walled structure and displays vme -type topology with point symbol of (33.43.58.6). The MOF has been used as catalyst for photodegradation of a model aromatic dye methyl violet (MV). The photocatalytic results indicate that 1 possess good photocatalytic property to degrade MV upto four consecutive cycles. The plausible active species involved during photodegradation have been assessed by using different scavengers and probable photocatalytic mechanism is explained using density of states calculations as well as the Hirshfeld surface analysis. A novel 3D Dy(III) double-walled structure constructed from a semi-rigid carboxylate functionalized triazole derivative ligand exhibited a stable activity for methyl violet (MV) degradation after four consecutive usages. The plausible mechanism was investigated. [Display omitted] [ABSTRACT FROM AUTHOR]

Ultrathin TiO 2 nanosheet with abundant Ti3+ is constructed as a photocatalyst for CO 2 conversion in the absence of any sacrificial reagents. The exposed Ti3+ as a Lewis base site may activate CO 2 to form bridging Ti···CO 2 −···Ti, resulting highly CH 4 yield via the synergistic effect of coordination-activation and photocatalysis. • Ultrathin TiO 2 nanosheets (NST) with abundant Ti3+ sites are constructed as a photocatalyst for conversion CO 2. • The catalyst (NST) exhibits a high yield (147.2 μmol g−1 h−1) and selectivity (96.8 %) for CH 4. • CO 2 would be selectively activated on the surface of NST via forming the bridging Ti···CO 2 −···Ti coordination species. • The synergistic effect about coordination-activation and photocatalysis can greatly enhance CH 4 yield efficiency. Ultrathin TiO 2 nanosheet (NST) with abundant Ti3+ sites is developed as a photocatalyst which exhibits a high yield (147.2 μmol g−1 h−1) and selectivity (96.8%) for CO 2 to CH 4. The results of in situ FTIR, in situ EPR and density functional theory (DFT) calculation suggest that CO 2 would be selectively activated on NST surface via forming the bridging Ti···CO 2 −···Ti coordination species which not only lowers the activation energy barrier, but also determines the selectivity of CH 4. Additionally, NST with the better separation and transfer ability for photogenerated electrons-holes can fleetly supply the electrons to CO 2 molecules for high efficiently producing CH 4 via the Ti-C coordination bond. Finally, a possible mechanism of the synergistic effect about coordination-activation and photocatalysis is discussed at a molecule level. This work would offer a perspective for designing an effective photocatalyst and tailoring the selectivity of products by coordination activation. [ABSTRACT FROM AUTHOR]

• Three new heterometallic chalcogenides were synthesized in a thiol-amine solvent mixture. • The thiol-amine solvent mixture was crucial to the crystal growths of these compounds. • Compound 1 displayed promising photocatalytic activity for degrading RhB under visible light irradiation. By using a n -butylamine (BA)-1,2-ethanedithiol (EDT) solvent mixture as reaction medium, three new heterometallic chalcogenides have been prepared, namely [HBA] 2.6 [In 2.6 Sn 1.4 Se 6 S 2 (1), [HBA] 0.8 HR - MP 2 [In 2.8 Sn 1.2 Se 6 S 2 (2) (R -MP = (R)-2-methylpiperazines) and [H 3 TAEA] 2 [InGe 4 S 11 (SH) 2 (OH)] (3) (TAEA = tris(2-aminoethyl)amine). Compounds 1 and 2 feature anionic two-dimensional [In x Sn 4 -x Se 6 S 2 x− layers built up by [M 4 Q 10 (M = In/Sn, Q = Se/S) T2 clusters. Protonated HBA+ and H R -MP+ cations serve as charge balance agents located between the layers. Compound 3 contains discrete [InGe 4 S 11 (SH) 2 (OH)]6− anionic clusters, in which the In3+ ion adopts a unique penta-coordination geometry with five S2− ions. These compounds were characterized by single crystal X-ray diffraction, powder X-ray diffraction, energy dispersive X-ray spectroscopy, solid-state UV–Vis diffuse reflectance spectroscopy, and thermogravimetric analyses. The steep UV–Vis absorption edges indicate the band gaps of 1.86 eV for 1 , 2.13 eV for 2 and 2.78 eV for 3. [ABSTRACT FROM AUTHOR]