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A novel thermo-responsive 2,9(10),16(17),23(24)-tetrakis[(3-carboxyacrylamide) phthalocyaninato] zinc (ZnPc)-g-TiO2-g-poly(N-isopropylacrylamide) (PNIPAM) photocatalyst modified with phthalocyanines was prepared. The photocatalyst exhibited thermo-responsive properties due to the introduction of PNIPAM, which performed recovery for reuse above the lower critical solution temperature (LCST, about 26 °C). ZnPc-g-TiO2-g-PNIPAM effectively expanded the light response range to the visible light region and inhibited the recombination of electron–hole pairs, which enhanced the performance of the photocatalyst. As expected, ZnPc-g-TiO2-g-PNIPAM (0.3 g/L) exhibited excellent photocatalytic performance for the removal of Rhodamine B (RhB, 1.0 × 10−5 mol/L) and methylene blue (MB, 1.0 × 10−5 mol/L) under visible light, which reached 97.2% and 88.6% at 20 °C within 40 min, respectively. Furthermore, the influence of temperature upon photocatalytic performance was also investigated. When the temperature increased from 20 °C to 45 °C, the removal of RhB decreased by approximately 53.8%. The stability of the photocatalyst demonstrated that the photocatalytic activity was still above 80% for the removal of RhB after 3 cycles. Above all, this work provided an intelligent thermally responsive photocatalyst based on phthalocyanine for water purification under visible light. [ABSTRACT FROM AUTHOR]

To design novel conjugated polymers and improve interfacial interaction with semiconductor is one of directions to develop high-efficient photocatalysts with harvesting photons and boosting catalytic activities. Herein, two novel linear conjugated polymers poly[(thiophene-ethylene-thiophene)-thiophene] (PTET-T) and poly[(thiophene-ethylene-thiophene)-thiophene-3-carboxylic acid] (PTET-T-COOH) were successfully synthesized by a simple Stille coupling reaction. Their heterojunction with TiO2, i.e, PTET-T/TiO2 (C1) and PTET-T-COOH/TiO2 (C2), exhibited outstanding photocatalytic activity for degrading Rhodamine B, methylene blue and tetracycline. The energetic "lock-in effect" between PTET-T-COOH and TiO2 through carboxyl groups and hydroxyl groups interaction has been proved to greatly improve the interface charge transfer ability and suppress the electron-hole recombination in PTET-T-COOH/TiO2. Thus, by regulating the dosage of polymers, the 15% PTET-T-COOH/TiO2 showed the optimized photocatalytic activity with excellent chemical stability, and its kinetic rate constant was determined to be 41.7 times of that of TiO2. This work provided a new effective strategy of designed and explored organic semiconductor-inorganic heterojunction photocatalysts with broaden absorption, repeatability and high-charge mobility. [ABSTRACT FROM AUTHOR]

Through the cooperation of atom transfer radical polymerization (ATRP) and the click reaction, star-shaped poly(N-isopropylacrylamide), namely, (ZnTHPP-(PNIPAM-ZnTPP)4) with 5,10,15,20-tetra(4-(2-bromoisobutoxy)phenyl)-21H,23H-zincporphyrin (ZnTHPP-4Br) as the core group and 5-(4-propargyloxyphenyl)-10,15,20-triphenylzinc-21H,23H-porphyrin (ZnTPP-Py) as the end group was prepared, and it was used as a photocatalyst for the degradation of Rhodamine B under visible light irradiation. The structure of the star-shaped polymer was characterized by FT-NIR, 1H NMR, UV-Vis and GPC analyses. The photocatalytic property study indicated that ZnTHPP-(PNIPAM-ZnTPP)4 had higher photocatalytic activity than the polymer ZnTHPP-(PNIPAM-Br)4 before the click reaction and could be recycled by warming. [ABSTRACT FROM AUTHOR]

Conjugated polymers consist of extended π-conjugated systems, which are a new generation of heterogeneous photocatalysts. Herein, a series of two-dimensional fully conjugated microporous polymers (benzobisoxazole-linked porphyrin-based conjugated microporous polymers, BBO-Por-CMP and BBO-MPor-CMPs, M = Zn, Cu, Ni) were designed and synthesized by using porphyrins as building block and benzobisoxazoles as bridge linker for the first time. They have three highlighted advantages for photocatalytic application, namely robust, non-toxic, visible-light active, making them attractive photocatalyst candidates when integrating with their intrinsic features. BBO-Por-CMP and BBO-MPor-CMPs with fully π-conjugated and rigid microporous networks efficiently improve light-harvesting capability in the long-wavelength visible light region. The bridge linker benzobisoxazole efficiently prevents the aggregation of porphyrins, increases the exposure of the majority of the porphyrin units to oxygen, and enhances photocatalytic capability. As a result, oxidants-free BBO-Por-CMP and BBO-MPor-CMPs enable efficiently degradation of high concentrations (25 mg/L) and wide range of dyes (RB, MB, MO) in a short time. Therefore, BBO-Por-CMP and BBO-MPor-CMPs can be considered as promising photocatalysts for dealing with dyes sewage. [ABSTRACT FROM AUTHOR]

ABSTRACT A series of well-defined linear poly( N-isopropyl acrylamide) with an asymmetrical zinc(II) porphyrin (ZnPor-PAM) end group was synthesized by atom transfer radical polymerization, wherein 5,10,15,20- tetra( p-bromopropanoyloxyethylphenyl) zinc porphyrin tripropionate was used as the initiator and CuBr/tris(2-dimeoethyl)amine was used as the catalyst system. The structure of the ZnPor-PAM was characterized by Fourier transform infrared spectroscopy and 1H-NMR. In addition, the polydispersity index (PDI) obtained by gel permeation chromatography indicated that the molecular weight distribution was narrow; thus, the polymerization was well controlled (1.05 < PDI < 1.21). Because of the incorporation of hydrophobic porphyrin, the lower critical solution temperature of ZnPor-PAM was lower than that of the N-isopropyl acrylamide homopolymer. Most interestingly, the ZnPor-PAM possessed remarkable photocatalytic activity for the oxidative degradation of methylene blue in the presence of hydrogen peroxide under visible-light radiation. Moreover, ZnPor-PAM could be reused through the uncomplicated procedure, which exploited the thermoresponsive properties of ZnPor-PAM without any significant loss in activity. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40523. [ABSTRACT FROM AUTHOR]

[Display omitted] • A day-night photocatalyst WO 3 -FePc with dual reaction centers was synthesized. • The catalyst has enhanced visible light response and effective charge separation. • The synergistic effect of dual reaction centers improves photocatalytic activity. • WO 3 -FePc can degrade pollutants under day-night cycle with recyclability. In this article, we presented a novel WO 3 -FePc day-night dual reaction centers photocatalyst covalently modified by iron-tetra (N -carbonylacrylic) aminephthalocyanine (FePc), in which WO 3 as an electron-storage reservoir and FePc as a photosensitizer and Fenton reaction center, which synergistically improve photocatalytic activity. The photocatalytic performance of WO 3 -FePc was evaluated using Rhodamine B (RhB) as a model pollutant, and it exhibited remarkable efficiency, with degradation of 93.0% RhB achieved under visible light irradiation for 60 min, and 40.4% RhB degraded in the dark, corresponding to approximately 12.4 times the performance of WO 3 and 7.8 times that of FePc. In addition, the removal rates of methylene blue (MB), tetracycline hydrochloride (TC•HCl) and K 2 Cr 2 O 7 (Cr (VI)) by WO 3 -FePc under visible light were 99.9%, 99.9% and 81.5% in 20 min, respectively. The rapid charge separation and the synergistic effect between the photocatalytic center and the Fenton center lead to excellent photocatalytic performance. This study prepared a highly efficient photocatalyst WO 3 -FePc that can act continuously during both day and night, and its distinctive day-night dual reaction center provides a new way to overcome the limitations of traditional photocatalytic technology. [ABSTRACT FROM AUTHOR]

Three-dimensional donor-acceptor (D-A) type conjugated porous polymers (CPPs) was designed and synthesized via imine condensation of copper tetraaminoporphyrin (CuTAPP) as donor and 1,3,5-tris-(4-formyl phenyl) triazine (TFPT) as acceptor, named as CuPT-CPP. The CuPT-CPP possesses a high specific surface area (73.7 m2/g) and excellent photophysical properties. The simultaneous introduction of the organometallic molecules and D-A structures in CuPT-CPP could be broadened the visible-light response range (400–800 nm) and facilitated efficient photogenerated carrier separation and transportation. As heterogeneous photocatalysts, CuPT-CPP has excellent photocatalytic performances under visible light irradiation, leading to excellent model pollutant rhodamine B degradation efficiency up to about 100% in 3 h, it has superb stability and reusability during the photocatalytic processes, and CuPT-CPP also exhibited broad substrate adaptability, which could photocatalytic degradation of methylene blue (MB), methyl orange (MO), and tetracycline hydrochloride (TC). This work indicates that three-dimensional D-A type porphyrin- and triazine-based CuPT-CPP has great potential in the practical application of photocatalysis. [Display omitted] • Donor-acceptor structural triazine- and porphyrin-based CPP were synthesized. • CuPT-CPP possesses a high specific surface area and excellent stability. • The donor-acceptor structure in CuPT-CPP facilitated efficient charge separation. • CuPT-CPP shows good performance in visible-light degradation of organic pollutants. [ABSTRACT FROM AUTHOR]

Metal phthalocyanines (MPcs) have attracted more and more attention in recent years for the catalytic degradation of pollutants in water driven by visible light. However, they are easy to aggregate in the aqueous phase and difficult to recycle, which seriously limits their photocatalytic activity and applicability. Introducing phthalocyanine into polymers may be an effective way to solve the above problems. Herein, three kinds of copolymers PNIPAM x - co -PDUPcZn y with different molecular weights and monomer ratios were synthesized by reversible addition-fragmentation chain transfer (RAFT) polymerization, with S-1-dodecyl-S′-(α,α'-dimethyl-α"-acetic acid)trithiocarbonate (DDMAT) as chain transfer agent, 3-undecenamide-9(10),16(17),23(24)-decyloxy‑zinc phthalocyanine (DUPcZn) and N -isopropyl acrylamide (NIPAM) as monomers, 2,2′-azobis(2-methylpropionitrile) (AIBN) as initiator. The polymerization process shows the characteristics of living polymerization, and the polymer dispersity index (PDI) values are <1.1. The three copolymers exhibit obvious thermo-responsive characteristics and the lower critical solution temperatures (LCSTs) are between 32.7 °C and 33.1 °C. The photocatalytic activity of the copolymers was evaluated by using 1,5-dihydroxynaphthalene (DHN) and Cr(VI) as model pollutants. It was found that the three copolymers had photocatalytic oxidation performance for DHN and photocatalytic reduction performance for Cr(VI), and their photocatalytic property was affected by the pH of the model pollutant solution and the catalytic temperature. Among them, PNIPAM 57 - co -PDUPcZn 7 exhibit a photocatalytic oxidation rate of 93.0% for DHN and the photocatalytic reduction rate of 70.0% for Cr(VI), respectively, under the visible light irradiation for 120 min at pH = 5 and 32 °C. More importantly, the homogeneous catalysis and heterogeneous recovery are achieved in the catalytic process through simple temperature regulation. In addition, the copolymers exhibited excellent chemical stability and reusability after three cycles. Finally, O 2 1/e− was determined to be the active species that plays a crucial role in the photocatalytic oxidation/reduction process, upon which a possible photocatalytic mechanism was proposed. This research provides a promising strategy for the synthesis of environmentally friendly visible light catalysts for the sewage (waste) water treatment. [Display omitted] • Novel unsymmetrical zinc phthalocyanine with alkenyl group has been synthesized. • A series of thermo-responsive copolymers PNIPAM x - co -PDUPcZn y were prepared. • The copolymers were prepared by RAFT polymerization. • The photocatalytic oxidation/reduction activity of the copolymers was evaluated. • The catalysts showed excellent catalytic activity without requiring any cocatalyst. [ABSTRACT FROM AUTHOR]

• A magnetic and thermosensitive hybrid organic/inorganic photocatalyst was prepared. • ZnTcPc sensitized TiO 2 to enhance photocatalysis activity. • PNIPAM grafting would improve photocatalytic dispersion in water. • The photocatalyst could be recovered by thermal and magnetic responses for reusing. A novel hybrid organic/inorganic magnetic and thermal dual-responsive core-shell green photocatalyst zinc-tetracarboxyl-phthalocyanine- g -Fe 3 O 4 @SiO 2 @TiO 2 - g -poly(N -isopropyl acrylamide) had been prepared. Firstly, Fe 3 O 4 @SiO 2 @TiO 2 (FST) was prepared with core-shell structure, then thermosensitive poly(N -isopropylacrylamide) (PNIPAM) immobilized on the surface of 3-(methacryloxypropyl)-trimethoxysilane (MPS) modified FST by radical polymerization. Below the lower critical solution temperature (LCST), PNIPAM was hydrophilic to ensure them disperse uniformly in aqueous solution, and above LCST, PNIPAM became hydrophobic to accelerate the separation of FST from water. Secondly, zinc-tetracarboxyl-phthalocyanine (ZnTcPc) grafted on the surface of FST- g -PNIPAM by ester bonds and sensitized TiO 2 to broaden absorption light range from ultraviolet to visible region to enhance photocatalytic activity. The photocatalytic test revealed that the decomposition rate of Rhodamine B (RhB) came to 91.8% after 60 min with ZnTcPc- g -FST- g -PNIPAM under visible light. When exposed under sun light, the degradation efficiency reached to 96.9%. It meant ZnTcPc- g -FST- g -PNIPAM was more suitable for organic pollutant degradation in nature. In addition, ZnTcPc- g -FST- g -PNIPAM performed efficient synergistic effect of thermal (>LCST) and magnetic responded recovery for reusing. And the degradation rate of RhB under recyclable photocatalyst was reduced 9.6% after 4 cycles. Above all, ZnTcPc- g -FST- g -PNIPAM would be an efficient photocatalyst with magnetic and thermal dual-responsive recovery used in water treatment. [ABSTRACT FROM AUTHOR]

In this study, TiO 2 nanoparticle-encapsulated ZIF-8/polyacrylonitrile (PAN)-derived porous carbon nanofibers (PCNFs) have been synthesized by combining electrospinning and hydrothermal methods, which were then sensitized with tetra-carboxyphenylporphyrin copper(Ⅱ) (CuTCPP) to obtain porous carbon nanofibers ternary photocatalyst (PCNFs@TiO 2 -CuTCPP) for photocatalytic degradation of pollutants. The structure and composition of the samples were characterized by XRD, FT-IR and XPS. The internal pore structure of PCNFs@TiO 2 -CuTCPP and the uniformity of the outer layer wrapped by TiO 2 nanoparticles can be observed by SEM and HRTEM. PCNFs@TiO 2 -CuTCPP has a high specific surface area (136.68 m2/g), which enables it to have excellent adsorption activity for model dye-Rhodamine B (RhB, 47.2 %, 4.7 × 10−4 mol/g), Methylene Blue (MB, 27.7 %, 2.8 × 10−4 mol/g) and Tetracycline hydrochloride (TC, 38.9 %, 3.1 × 10−4 mol/g) within 30 min. Photocatalytic experiments showed that the degradation rates of RhB and MB by PCNFs@TiO 2 -CuTCPP as photocatalyst were 95.4 %, 92.8 % and 89.9 %, respectively, after 180 min of visible light irradiation. PCNFs@TiO 2 -CuTCPP was continuously reused for four cycles without significant photoactivity loss and structural changes. Furthermore, the crucial role of . O 2 −, 1O 2 and . OH were confirmed by active species capture experiments, and the photocatalytic mechanism under visible light was proposed. Above all, this study prepared a recyclable TiO 2 -based porous carbon nanofibers photocatalyst and provided a new idea for the effective modification of TiO 2 in the field of photocatalysis. • CuTCPP-sensitized TiO 2 @PCNFs was prepared for visible light photocatalysis. • PCNFs@TiO 2 -CuTCPP has large specific surface area and porous structure. • PCNFs@TiO 2 -CuTCPP could effectively adsorb RhB, MB and TC in dark. • PCNFs@TiO 2 -CuTCPP could efficiently degrade RhB, MB and TC under visible light irradiation with recyclability. [ABSTRACT FROM AUTHOR]

A series of metallophthalocyanine-based conjugated microporous polymers (MPc-CMPs, M = Co, Cu, Zn) were synthesized and used for the photodegradation of organic pollutants for the first time. The as-obtained MPc-CMPs were characterized by UV-vis spectroscopy, Fourier transform infrared spectra (FTIR), scanning electron microscope (SEM). Their photocatalytic activities were assessed by the photodegradation of RhB in the presence of H 2 O 2 under visible light irradiation. Moreover, the possible mechanism to predict this reaction pattern was proposed. As a result, the as-obtained MPc-CMPs, especially CoPc-CMP, exhibit excellent photocatalytic efficiency, recyclability and stability. These results indicate that the MPc-CMPs are potentially applicable in the environmental purification of organic pollutants in the industrial wastewater. [ABSTRACT FROM AUTHOR]

[Display omitted] • Porphyrin- and Tetraphenylethylene-based TP-COF as photocatalyst was synthesized. • The TP-COF with a large surface area had a good photoelectric response. • The separation and transfer of photo-induced electron-hole pairs is significantly improved in TP-COF. • The photocatalysts TP-COF showed high stability and durability in H 2 evolution. A crystalline, bi-photoelectric structural unit 2D periodic square lattice covalent organic framework was designed and target synthesized by the Schiff base condensation between 1,1,2,2-tetra(4-formyl-(1,1′-biphenyl)) ethene and 5,10,15,20-tetrakis(4-amino phenyl)-21H,23H-porphyrin with AA stacking structures, named as TP-COF. The TP-COF exhibited good photoelectric response combined with good crystallinity and high specific surface area (1812 m2 g−1). TP-COF with an optical bandgap of 1.80 eV can be used as a visible light responsive photocatalyst, and the speed of hydrogen evolution by TP-COF could achieve up to 58.4 μmol g−1h−1 under visible light irradiation. The efficient photocatalysis performance could be attributed to the photogenerated charge separation and transport of TP-COF by the fluorescence resonance energy transfer (FRET) from tetraphenylethylene to porphyrin. The successful preparation of this type of COF according to the designed structure provides a new way to realize photocatalyst targeting synthesis for better photocatalysis. [ABSTRACT FROM AUTHOR]

Abstract: A series of well-defined star-shaped poly(N-isopropylacrylamide) (ZnTHPP-PAM) with zinc-porphyrin as the core was synthesized by atom transfer radical polymerization (ATRP). Zinc(II)meso-tetra(p-bromopropionylphenyl)porphyrin (ZnTHPP-Br) was employed as the initiator, and CuBr/tris(2-dimeoeth-yl)amine(Me6TREN) was selected as the catalyst system. The structures of the target polymers were characterized by FT-IR and 1H NMR. The polydispersity index (PDI) was obtained by gel permeation chromatography (GPC), indicating that the molecular weight distribution was narrow and the polymerization was well controlled. The lower critical solution temperatures (LCST) for the aqueous solutions of ZnTHPP-PAM were generated by using turbidimetry method. The result exhibited lower value as compared to that of NIPAM homopolymer, which was arose from the incorporation of the hydrophobic porphyrin core. The photocatalytic activity of ZnTHPP-PAM was verified by the degradation of Methylene Blue in the presence of hydrogen peroxide under visible light. It was worth noting that the catalytic efficiency was higher at the LCST of the polymer, which benefited to the reuse of the photocatalyst. [Copyright &y& Elsevier]

[Display omitted] • A magnetic hybrid organic/inorganic photocatalyst was successfully prepared. • ZnIn 2 S 4 and phthalocyanines modified TiO 2 to broaden the range of light absorption. • The photocatalyst showed excellent activity for pollutants removal. • The synergetic photocatalytic mechanism was projected. This study synthesized a recyclable dual-responsive core–shell photocatalyst Fe 3 O 4 @SiO 2 @TiO 2 @ZnIn 2 S 4 /ZnPc (FSTZP) used for hexavalent chromium (Cr (VI)) reduction. Core-shell Fe 3 O 4 @SiO 2 @TiO 2 (FST) was prepared and modified with ZnIn 2 S 4 and zinc-tetra (N -carbonylacrylic) aminephthalocyanine (ZnPc) to obtain FSTZP and characterized by XRD, XPS, SEM, HRTEM and UV–vis DRS. In FSTZP, ZnIn 2 S 4 could provide more adsorption active sites and promote charge-carrier separation; ZnPc would efficiently use visible light to transfer energy. Both of ZnIn 2 S 4 and ZnPc in FSTZP could improve the light-harvesting resulting in excellent photocatalytic performance of FSTZP towards Cr (VI) reduction and pollutant degradation. The highest reduction efficiency of Cr (VI) by FSTZP (0.3 g/L) was up to 96.4% in 60 min at pH = 6. The removal efficiencies of Rhodamine B (RhB), Methylene blue (MB), Methyl Orange (MO) and Tetracycline hydrochloride (TC•HCl) by FSTZP (0.3 g/L) under visible light were 99%, 99%, 95% and 86% in 40 min at pH = 6. Meanwhile, almost all of Cr (VI) and organic molecules in the coexistence system could be removed by FSTZP under visible light. FSTZP also presented the adsorption property and the mechanism of dual-responsive FSTZP for Cr (VI) reduction and organic pollutants removal was explored. Moreover, as an efficient photocatalyst, FSTZP still maintained stability after reused for fourth photocatalytic cycle by magnetic recovery. This study was devoted to develop an efficient photocatalyst suitable for removing Cr (VI) and organic pollutants. [ABSTRACT FROM AUTHOR]