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A new magnetically responsive three-component nanocomposite consisting of ZnFe 2 O 4 (ZnFe), polythiophene (PTh) and porphyrin was successfully prepared by coating of ZnFe 2 O 4 nanoparticles with polythiophene and subsequent sensitizing with tetrakis(4-carboxyphenyl)prophyrin (TCPP). The prepared TCPP/ZnFe 2 O 4 @Polythiophene nanocomposite (TCPP/ZnFe@PTh NC) was investigated by X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FT-IR), Energy-dispersive X-ray spectroscopy (EDX), scanning electron microscopy imaging (SEM) and vibrating sample magnetometer (VSM). Diffuse reflectance spectroscopy (DRS) was used to find the photocatalytic ability of this nanocomposite. In addition, photocatalytic–adsorption activities of prepared samples were carried out for removal of methyl orange (MO), methylene blue (MB) and mixture of MB and MO under visible LED lamp light and sunlight irradiation. The results indicated that the synthesized nanocomposite not only shows excellent photocatalytic and adsorption activity for removal of MO and MB, respectively, but also can be separated easily by an external magnet and reused twice more. [ABSTRACT FROM AUTHOR]

A simple one-pot hydrothermal method was successfully used to synthesize p-n heterojunction Mn3O4/BiVO4 composites with different contents of BiVO4. The experimental results show that the as-prepared p-n heterojunction Mn3O4/BiVO4 composite exhibited higher visible light photocatalytic activity for the degradation of model dye methylene blue than the pure BiVO4 and Mn3O4 crystal under irradiation of 5 W white LED lamp. The enhanced photocatalytic efficiency is due to a large number of p-n heterojunctions in Mn3O4/BiVO4 composites, which effectively reduces the recombination of the electrons and holes by charge transfer from n-type BiVO4 to p-type Mn3O4 crystals. The prepared p-n heterojunction Mn3O4/BiVO4 composite was functionalized with cobalt, zinc, copper, and tin complexes of porphyrin. The energy diagrams of these prepared compounds were calculated via the electrochemical investigations and the electron transfer mechanism was discussed in details. The photocatalytic efficiency of the functionalized nanocomposites enhances significantly compared to the p-n heterojunction Mn3O4/BiVO4 under visible light irradiation. Between the prepared compounds, BiVO4/Mn3O4-CoTCPP shows higher photocatalytic activity. This compound can destruct 98% of dye pollutant in 180 min under irradiation of 5 W white LED lamp. Furthermore, this photocatalyst shows proper stability after four cycle degradation test. © 2017 American Institute of Chemical Engineers Environ Prog, 36: 1439-1448, 2017 [ABSTRACT FROM AUTHOR]

In this research, dipeptide (his-β-alanine) and porphyrin derivatives were choosen for comparing chelating ability of toxic metals such as Al3+, Cu2+, Hg2+ and Pb2+ in-vitro. The reason for choosing these two compounds is that both of them are naturally present in biological systems and comparison of chelating ability of these two compounds has not yet been done. Synthesis and comparison of kinetic study of dipeptide (his-β-alanine), meso-tetrakis(4- trimethylanilinium) porphyrin (TAPP) and Tetrakis(4-sulfonatophenyl)porphyrin (TPPS4) were carried out by our team. In addition, cytotoxicity assays of metals and chelators were also performed using methylthiazoletetrazolium (MTT) test. Furthermore we investigated the protective effect of chelators against cytotoxicity, induced by differenrt toxic metals such as Al3+, Cu2+, Hg2+ and Pb2+ on human lymphocytes. EC50 values on human lymphocytes obtained after 12 h. incubation for Al3+, Cu2+ and Hg2+ were 30, 51, 3 μM respectively and for Pb2+ no cytotoxicity was observed on human lymphocyte up to 1000 μM concentration. EC50 obtained for chelators dipeptide, TPPS4 and TAPP were 948, 472 and 175 μM respectively. Pretreatment of human lymphocyte with subtoxic concentations of chelators reduced toxicity of the metals against human blood lymphocytes. [ABSTRACT FROM AUTHOR]

To use the visible light in photodegradation reactions efficiently, graphene-TiO2 nanocomposite was photosensitized using tetrakis(4-carboxyphenyl)porphyrin. To investigate the effect of graphene as well as dye sensitization on the photoactivity of the synthesized photocatalyst, photocatalytic properties and photocurrent responses of the prepared samples were examined under visible light irradiation. A twofold increase of photocurrent response in the TG nanocomposite photosensitized with porphyrin (TGP) compared to TG (3%) nanocomposite provides an evidence of the effective influence of the porphyrin photosensitizer in the visible light photoactivity enhancement. There is a complete correspondence between the photocatalytic activity and photocurrent response of the photocatalysts. The photocatalytic properties of the photocatalysts were carried out in the degradation of methyl orange and bisphenol A under visible light irradiation. It was determined that TGP compound was stable after photocatalytic process and degraded 93% of methyl orange and 85% of bisphenol A in 240 min under visible light irradiation. Furthermore, the mechanism of investigation of the photocatalytic process determines that O-2 and OH are the main reactive species for degradation of methyl orange and bisphenol A over the TGP compound under visible light irradiation. [ABSTRACT FROM AUTHOR]

In this study, the SBA-16 was synthesized and modified by 3-aminopropyltriethoxysilane. Then, the copper (II) meso-tetrakis(4-chlorophenyl)porphyrin (CuTClPP) was immobilized into SBA-16 (CuTClPP@SBA-16) by using ship in a bottle method. The synthesized mesoporous materials and heterogeneous catalyst were characterized by Fourier transform infrared (FT-IR), diffuse reflectance spectroscopy (DRS), X-Ray diffraction (XRD), N 2 adsorption–desorption (BET), elemental analysis (CHN), electron disperse X-ray (EDX), inductively coupled plasma (ICP-AES) and scanning electron microscope (SEM). The catalytic activity of the obtained catalyst was examined in the oxidation of cyclohexene with t-butyl hydroperoxide (TBHP) and hydrogen peroxide (H 2 O 2 ) as oxidants. The obtained products were determined by using gas chromatography (GC). The effect of visible light on oxidation efficiency was evaluated and results showed that the activity of catalyst increased under visible light. In addition, leaching and recycling experiments revealed that the catalyst can be repeatedly applied for cyclohexene oxidation for three successive cycles. [ABSTRACT FROM AUTHOR]

In the present work, the Fe 3 O 4 nanoparticles were synthesized via a green and facile mechanochemical method. Then 5,10,15,20-meso-tetrakis(4-carboxyphenyl)porphyrin (TCPP) was immobilized on surface of the Fe 3 O 4 nanoparticles. The prepared nonocomposite was characterized by FT-IR, XRD, DRS, VSM and SEM images and their photocatalytic activity was investigated in the removal of methylene blue from aqua media. [ABSTRACT FROM AUTHOR]