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[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]

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]

• 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]

• 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 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]

[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]

• 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]