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A green approach for the biosynthesis of silver nanoparticles (AgNPs) was developed using Diplazium esculentumaqueous extract as green reductant. The bio-stabilized AgNPs were characterized by UV–visible spectroscopy (UV–Vis), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), dynamic light scattering (DLS), and high-resolution transmission electron microscopy (HRTEM). The formation of AgNPs was indicated by the colour change and the absorption peak at 449 nm in the UV–Vis spectrum. FTIR spectral analysis suggested the possible biomolecules associated with the reduction of silver ions. The crystalline and face-centered cubic (fcc) structure of AgNPs was obtained by the XRD study. HRTEM analysis showed that the biosynthesized AgNPs composed of quasi-spherical, hexagonal, and ellipsoidal shapes with an average particle size of 23.385 ± 8.349 nm. The biosynthesized AgNPs exhibited good catalytic activity up to 91% reduction of Methylene blue (MB), which followed a reductive pathway rather than a photocatalytic route. The catalytic reduction follows a pseudo-first-order reaction with a rate constant of 0.1051 min-1. The disc diffusion technique (DDT) and minimal inhibitory concentration (MIC) results showed significant antibacterial capability against Gram-positive (Escherichia coliATCC 11,229) and Gram-negative (Staphylococcus aureusATCC 6538) bacteria.

•Synthesis of differently shaped Au/Cu2O (metal/semiconductor) core/shell nanostructures.•Effect of nanoparticle morphology and shell thickness on optical properties of Au/Cu2O nanostructures.•Correlation of photoluminescence analyses of core/shell nanostructures with their photocatalytic activities.•Nanostructures with more {100} catalytically inactive sites reveal a comparatively sharp emission peak.

Palladium (II) complex containing picoline thiourea (Pd-PTu) was prepared by reacting bis (benzonitrile) palladium (II) chloride (Pd-PhCN) with N’-2-(5-picolyl)-N-4-bromobenzoylthiourea (PTu). All synthesized compounds have been characterized via several selected typical spectroscopic and analytical techniques namely elemental analysis, Infrared (IR) spectroscopy, Ultraviolet-visible (UV-Vis) spectroscopy, Nuclear Magnetic Resonance (1H and 13C NMR) and gas chromatography-flame ionization detector (GC-FID). For Pd-PTu, IR spectrum showed significant shift in the ν (C=N) on the pyridine ring and ν (C=S) stretching vibration at around 30cm-1 compared to the free ligand. The finding indicated that the expected coordination of ligand to the palladium metal centre took place via N and S atoms. The catalytic reaction was monitored using GC-FID with conversion of 83.81 %, proved that Pd-PTu can be used as an ideal homogenous catalyst in any Heck cross-coupling reactions in the near future.

In this work, a new photocatalyts In(0.1),Cu(x)-ZnS (x=0.01, 0.03, 0.05) is successfully synthesized using simple hydrothermal method. The physical and chemical properties of the In and Cu co-doped ZnS photocatalyst were characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), diffuse reflectance UV-visible spectroscopy (DR UV-visible) and photoluminescence spectroscopy (PL). The photocatalytic activity of the as-prepared In and Cu co-doped ZnS for hydrogen production from water with Na2SO3and Na2S as sacrificial agent under visible light irradiation (λ ≥ 425nm) was investigated. The presence of co-dopants facilitated the separation of electron-hole as well as increases the visible light absorption. The absorption edge of the co-doped ZnS photocatalyst shifted to longer wavelength as the amount of Cu increases. This indicates that the absorption properties depended on the amount of Cu doped. The photocatalytic activity of single doped In(0.1)-ZnS was significantly enhanced by co-doping with Cu under visible light irradiation. The highest photocatalytic activity was observed on In(0.1),Cu(0.03)-ZnS with the hydrogen production rate of 131.32µmol/h under visible light irradiation. This is almost 8 times higher than single doped In(0.1)-ZnS.

Here phosphorescent trinuclear copper (I) pyrazolate complexes ([Cu3Pz3]), synthesized from 3,5-dimethyl and 4-(3,5-dimethoxybenzyl)-3,5-dimethyl pyrazole ligands for complexes [Cu3Pz3]1 and [Cu3Pz3]2, were successfully impregnated into TiO2 with concentration of 0.1 mol%. These luminescent photocatalyst composites ([Cu3Pz3]1 or 2/TiO2) gave 60% and 49% of dichlorophenoxyacetic acid (2,4-D) degradation after 1 h for [Cu3Pz3]1/TiO2 and [Cu3Pz3]2/TiO2, while TiO2 only showed 48%. The higher activity observed on [Cu3Pz3]1/TiO2 than the TiO2 would come from the efficient reduction of electron-hole recombination, while less dispersion of complex [Cu3Pz3]2 with more rigid structure compared to complex [Cu3Pz3]1 gave similar activity of the [Cu3Pz3]2/TiO2 to the TiO2.

A series of copper oxide loaded TiO2was prepared by a photodeposition method. It was clarified through XANES that the added copper species solely existed as highly dispersed Cu(ii) and it remained as Cu(ii) after the photocatalytic reaction. The prepared CuO/TiO2with various contents (0.1–5 mol%) were used as photocatalysts for 2,4-dichlorophenoxyacetic acid (2,4-D) degradation under UV, visible, and solar simulator irradiation. Under UV light irradiation, the photocatalytic activity of 2,4-D decomposition increased by a maximum factor of 4.3 compared with unmodified TiO2when TiO2was loaded with 0.75 mol% CuO. In contrast, under visible light and solar simulator irradiation, the optimum loading of CuO was much lower (0.1 mol%) and enhancements of 22.5 and 2.4 times higher activities were observed, respectively. These results showed that the different masking effects due to the different light sources led to different optimum amounts of CuO, and the added CuO mostly contributed to the visible light activity of TiO2. Therefore, in addition to the increased charge separation and improved visible light absorption, the masking effect shall also be considered in designing highly active photocatalysts under visible and solar light irradiation.

Titanium dioxide (TiO2) has been recognized as an active photocatalyst for degradation of various organic pollutants. In this study, in order to improve the photocatalytic activity of TiO2, the effect of lanthanum oxide modification was investigated by using commercial P25 as the benchmark. Lanthanum oxide/P25 TiO2 composites with 0.1, 0.5, 1 and 5 mol% of La loadings were prepared via an impregnation method. The resultant composites were characterized by X-ray diffraction (XRD), UV-Vis absorption spectroscopy, transmission electron microscopy (TEM), inductively coupled plasma optical emission spectrometry (ICP-OES) and electrochemical impedance spectroscopy (EIS). It was confirmed that the addition of lanthanum oxide did not much affect the crystallinity, crystal structure and the morphology of P25 TiO2. The catalytic activities of the lanthanum oxide/P25 TiO2 catalysts were tested by using 2,4-dichlorophenoxyacetic acid (2,4-D) as the test pollutant and UV light as the irradiation source. The reaction was caried out for 1 hour at room temperature and the percentage removal was determined using a UV spectrophotometer. The results showed that La loading was an important factor that influenced the photocatalytic activity of the composites. After 1 hour reaction, the best catalyst with 0.1 mol% of La loading showed 24% higher photocatalytic activity than the unmodified P25 TiO2 catalyst. It is shown by EIS that the enhanced photocatalytic activity of the composites was due to the ability of lanthanum oxide in improving the charge separation of the photogenerated electron-hole pairs in TiO2.

In and Ag co-doped ZnS photocatalysts were successfully prepared by hydrothermal method to extend the light absorption of ZnS to the visible light region. The concentration of In was constant while for Ag was varied to optimize the photocatalytic activity. The In and Ag co-doped ZnS photocatalysts showed smaller band gap energy compared to single doped In (0.1)-ZnS and undoped ZnS. The photocatalytic activity of In and Ag co-doped ZnS photocatalysts was evaluated from the amount of hydrogen produced. The hydrogen evolution rate from aqueous solution containing Na2SO3 and Na2S as sacrificial reagent under visible light irradiation obtained from In and Ag co-doped ZnS is higher compared to the single doped In (0.1)-ZnS when optimum amount of Ag dopant was added. The highest photocatalytic activity is observed for In (0.1),Ag (0.01)-ZnS with hydrogen production rate of 26.82 μmol/h. The higher performance of this photocatalyst is ascribed to the extended visible light absorption, efficient charge separation as well as improved electron transfer associated with synergistic effect of appropriate amount of In and Ag co-doped ZnS.

Here chemosensor materials of trinuclear copper (I) pyrazolate complexes have been successfully synthesized and isolated using two types of 3,5-dimethyl and 4-(3,5-dimethoxybenzyl)-3,5-dimethyl pyrazole ligands. Upon excitation at 280 nm, the resulting trinuclear 3,5-dimethyl copper (I) pyrazolate complex (complex A) and trinuclear 4-(3,5-dimethoxybenzyl) copper (I) pyrazolate complex (complex B) showed emission bands centered at 590 and 604 nm, respectively. These results were in good agreement with their greenish-white powders and it is characteristic of phosphorescent metal complexes from the weak Cu (I)-Cu (I) metallophilic interaction. Upon direct or stepwise exposure to ethanol vapor with series of concentrations (12.5, 25, 50, 100, 150 and 200 μL in 22 mg of chemosensor), the emission of chemosensor complex A was not shifted even after 1 d. Interestingly, chemosensor complex B showed gradually changes in both emission band with shifting from 602 to 552 nm and color with changing from orange to green under Ultra-violet (UV) hand lamp (254 nm) at the dark room due to the attachment of benzyl ring to the pyrazole ligand. This positive response for chemosensor complex B was reversible; hence, this optical phosphorescent material can be used for developing vapochromic sensors of ethanol.

Zinc sulfide (ZnS) has been reported to act as a photocatalyts to reduce water to hydrogen. However, ZnS could not work under visible light irradiation due to its large band gap energy. In order to improve the performance of ZnS, Ga and Sn were doped to ZnS. The series of Ga (0.1),Sn (x)-ZnS with various amounts of Sn (x) was prepared by hydrothermal method. XRD patterns suggested that the addition of Ga might reduce the crystallinity of ZnS, suggesting that Ga might inhibit the crystal growth or agglomeration of ZnS. On the other hand addition of Sn did not much affect the structure of the Ga (0.1)-ZnS. The DR UU-visible spectra confirmed the red shift of the absorption edge with the addition of Ga due to the reduced band gap energy, while the addition of Sn did not much shift the absorption edge of the Ga (0.1)-ZnS to longer wavelength. FESEM images showed that all the prepared samples have sphere-shaped particles and no remarkable change was observed with the addition of Ga or Sn. The photocatalytic hydrogen production from water was carried out at room temperature in the presence of sacrificial agent under visible light irradiation. While ZnS did not show activity under visible light, all the prepared Ga (0.1)-ZnS and Ga (0.1),Sn (x)-ZnS samples exhibited photocatalytic activity for hydrogen production. The highest hydrogen production was achieved on Ga (0.1),Sn (0.01)-ZnS, which activity was ca. three times higher than that of the single doped Ga (0.1)-ZnS. This study clearly showed that Sn acted as a good co-dopant to increase the photocatalytic activity of Ga (0.1)-ZnS for hydrogen production from water under visible light irradiation.

Herein we report the first example of benzene-1,3,5-tricarboxamide bearing hydrophobic aminododecane side chains (1) which spontaneously forms supramolecular network by a hydrogen bonding interaction. The compound 1 was synthesized by Schotten-Baumann reaction of 1,3,5-benzenetricarbonyl trichloride and 1-aminododecane in the presence of N,N-diisopropylethylamine. Nuclear Magnetic Resonance (NMR), Mass Spectrometry (MS), and Fourier Transform Infrared (FTIR) spectroscopies have proved the successful synthesis of 1 in 93% as white powder solid. The supramolecular organization was successfully utilized for sensing of nitrate anions by deformation of the hydrogen bonding to form inactive nitroso groups.

A series of In0.1SnxZn0.85-2xS solid solutions was synthesized by hydrothermal method and employed as photocatalyst for photocatalytic hydrogen evolution under visible light irradiation. The structures, optical properties and morphologies of the solid solutions were studied by X-ray diffraction, diffuse reflectance UV–visible spectroscopy and field emission scanning electron microscopy. From the characterizations, it was confirmed that In0.1SnxZn0.85-2xS solid solution can be obtained and they have nanosized particles. The highest photocatalytic activity was observed on In0.1Sn0.03Zn0.79S photocatalyst, with average rate of hydrogen production 3.05 mmol/h, which was 1.2 times higher than the In0.1Zn0.85S photocatalyst.

Treatment of Z-PPh2CH2C(But)=NNH2with 4-methylphenylthiomethyl methyl ketone gave the thioether azine phosphine Z,E-PPh2CH2C(But)=N-N=C(Me)CH2S(C6H4Me-4) 1, which with H2O2gave the corresponding phosphine oxide 2. Treatment of 1with [Mo(CO)3(η6-cht)] or [W(CO)3(NCEt)3] gave the yellow tricarbonyl complexes fac-[M(CO)3{PPh2CH2C(But)=N-N=C(Me)CH2S(C6H4Me-4)}] 3a(Mo) or 3b(W), respectively. Treatment of 1with [Mo(CO)4(nbd)] gave the pale yellow tetracarbonylmolbdenum(0) complex [Mo(CO)4{PPh2CH2C(But)=N-N=C(Me)CH2S(C6H4Me-4)}] 4, in which the ligand 1is bidentate through P and N. Oxidation of either 3aor 4with 1 equivalent of bromine gave the orange neutral seven-coordinate dicarbonylmolybdenum(II) complex [MoBr2(CO)2{PPh2CH2C(But)=N-N=C(Me)CH2S(C6H4Me-4)}] 5, whereas the tungsten complex 3bwith 1 equivalent of bromine gave the seven-coordinate tricarbonyltungsten(II) cation [WBr(CO)3{PPh2CH2C(But)=N-N=C(Me)CH2S(C6H4Me-4)}]+isolated as the PF6salt 6. Treatment of 1with [PtCl2(NCMe)2]gave the yellow dichloroplatinum(II) complex [PtCl2{PPh2CH2C(But)=N-N=C(Me)CH2S(C6H4Me-4)}] 7, in which 1is bidentate through P and N. When 7was treated with NH4PF6in methanol it gave the terdentate salt [PtCl{PPh2CH2C(But)=N-N=C(Me)CH2S(C6H4Me-4)}]PF68a. Deprotonation of 7with NEt3-NaOH gave the orange neutral chloroplatinum(II) complex [PtCl{PPh2-CH2C(But)N-NC(Me)=CHS(C6H4Me-4)}] 9, containing a terdentate ene-hydrazone phosphine ligand. This neutral complex 9was reprotonated using HBF4to give the BF4salt 8b. Treatment of the phosphine 1with [PtMe2(cod)] gave the white dimethylplatinum(II) complex [PtMe2{PPh2CH2C(But)=N-N=C(Me)CH2S(C6H4Me-4)}] 10, containing the bidentate azine ligand. Treatment of 10with MeI gave the white platinum(IV) iodide salt fac-[PtMe3{PPh2CH2C(But)=N-N=C(Me)CH2S(C6H4Me-4)}]I 11ain which the azine is terdentate. When 11awas treated with NH4PF6in MeOH the PF6salt 11bwas obtained. Treatment of 10with picric acid gave the yellow methylplatinum(II) picrate salt [PtMe{PPh2CH2C(But)=N-N=C(Me)CH2S(C6H4Me-4)}][OC6H2(NO2)3-2,4,6] 12and methane. Infrared, 31P–[1H], 1H, and some 13C–[1H] NMRdata are given. Keywords: azine phosphine, thioether, metal-carbonyls, platinum.

Titanium dioxide (TiO2) is well-known as an active photocatalyst for degradation of various organic pollutants. Over the years, a wide range of TiO2 nanoparticles with different phase compositions, crystallinities, and surface areas have been developed. Due to the different methods and conditions used to synthesize these commercial TiO2 nanoparticles, the properties and photocatalytic performance would also be different from each other. In this study, the photocatalytic removal of 2,4-dichlorophenoxyacetic acid (2,4-D) and 2,4,5- trichlorophenoxyacetic acid (2,4,5-T) was investigated on commercial Evonik P25, Evonik P90, Hombikat UV100 and Hombikat N100 TiO2 nanoparticles. Upon photocatalytic tests, it was found that overall, the photocatalytic activities of the P25 and the P90 were higher than the N100 and the UV100 for the removal of both 2,4-D and 2,4,5-T. The high activities of the P25 and the P90 could be attributed to their phase compositions, which are made up of a mixture of anatase and rutile phases of TiO2. Whereas, the UV100 and the N100 are made up of 100% anatase phase of TiO2. The synergistic effect of the anatase/rutile mixture was reported to slow down the recombination rate of photogenerated electron-hole pairs. Consequently, the photocatalytic activity was increased on these TiO2 nanoparticles.

In this work, suppression of the charge recombination on the titanium dioxide (TiO2) was reported by the addition of copper oxide (CuO), which led to a higher activity of TiO2 for removal of 2,4-dichlorophenoxyacetic acid (2,4-D) herbicide. A series of CuO/TiO2 with CuO loadings of 0.1-1 wt% was prepared through a co-precipitation method. X-ray diffraction patterns revealed that the presence of CuO could not be detected as the low loading amount of CuO might have good dispersion on the surface of TiO2. Diffuse reflectance UV-visible spectra suggested that low loading amount of CuO did not influence the optical property of TiO2. Fluorescence spectroscopy revealed that TiO2 possessed a dominant emission peak of 407 nm at an excitation wavelength of 218 nm. The increasing loading amount of CuO decreased the emission intensity of TiO2, suggesting the successful reduction of charge recombination. After irradiation under UV light for 1 h, CuO(0.1 wt%)/TiO2 gave the highest percentage removal of the herbicide among the samples. The optimum loading amount of CuOmight improve the charge separation and reduce the electron-hole recombination on TiO2 without blocking the active sites, thus leading to the improved photocatalytic activity. This work showed that CuO/TiO2 is a potential photocatalyst for environmental remediation.