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The construction of heterojunction between semiconductor is an effective technology to enhance its photocatalytic activity using solar energy. In this paper, a series of BiPO4/Bi2MoO6 heterostructures with different mole ratio of Mo:P were successfully synthesized via one‐pot solvothermal method. Photocatalytic activity of all samples were investigated by degrading methylene blue (MB) under visible light. Among the catalysts, BMoP‐1‐3 sample with oxygen vacancy has excellent photocatalytic activity due to improving its light harvesting and charge separation by establishment of Z‐scheme system heterostructure, which is 1.65 and 1.22 times that of pure BiPO4 and Bi2MoO6, respectively. [ABSTRACT FROM AUTHOR]

PDMAEMA‐b‐PMAA block copolymers were prepared by the sequential RAFT polymerization of DMAEMA and tBMA, followed by hydrolysis. Phosphotungstic acid (HPW) was anchored to the PDMAEMA blocks through electrostatic interactions and the as‐obtained HPW/PDMAEMA‐b‐PMAA was added to the synthesis of ZIF‐8. During the formation of ZIF‐8, the PMAA blocks coordinated to the Zn2+ ions through their carboxy groups, along with the HPW groups that were anchored to the PDMAEMA blocks. In this way, the block copolymer could consolidate the interactions between HPW and ZIF‐8 and prevent the leakage of HPW. Finally, the HPW/PDMAEMA‐b‐PMAA/ZIF‐8 ternary lamellar composite was obtained and the structure of the HPW/PDMAEMA‐b‐PMAA/ZIF‐8 hybrid material was characterized by using powder X‐ray diffraction (PXRD), X‐ray photoelectron spectroscopy (XPS), and scanning electron microscopy (SEM). As a photocatalyst, the HPW/PDMAEMA‐b‐PMAA/ZIF‐8 ternary lamellar composite showed excellent photoactivity for the degradation of methylene blue (MB). The rate of degradation of MB was 0.0240 min−1, which was 7.5‐times higher than that of commercially available P25 (0.0032 min−1). In the presence of H2O2, the kinetic degradation parameters of the composite reached 0.0634 min−1, which was about 19.8‐times higher than that of P25. Block party: A HPW/PDMAEMA‐b‐PMAA/ZIF‐8 ternary lamellar composite was designed and synthesized. As a photocatalyst, the HPW/PDMAEMA‐b‐PMAA/ZIF‐8 ternary lamellar composite showed excellent photoactivity toward the degradation of methylene blue. The rate of degradation of MB was 0.0240 min−1, which was 7.5 times that of the commercially available P25 (0.0032 min−1). In the presence of H2O2, the kinetic degradation parameters of the composites reached 0.0634 min−1, which is about 19.8 times that of P25. [ABSTRACT FROM AUTHOR]

Polyaniline (PANI) chains were grafted at the edge of graphene oxide (GO) sheets by in situ chemical oxidation polymerization with the p‐phenylenediamine attached to GO sheets as anchor sites. The structure and morphology of the GO‐PANI composite were characterized by Fourier‐transform infrared spectroscopy (FTIR) and Raman spectroscopy, thermogravimetric analysis, X‐ray diffraction, elemental analysis, and transmission electron microscopy. The GO‐PANI were used to adsorb Pb(II) and methylene blue (MB) from aqueous solution. The results showed that the adsorption kinetics and isotherms followed pseudo‐second‐order and Langmuir isotherm model, respectively. GO‐PANI exhibited the maximum adsorption capacity for Pb(II) (1416 mg/g) compared with other absorbents. The process of adsorption for Pb(II) onto GO‐PANI is spontaneous and endothermic at 288, 298, and 308 K. In mixed system, the adsorption capacity for MB and Pb(II) onto PANI‐GO achieved 544 and 1004 mg/g, respectively. This study provides a promising PANI‐GO composites with an efficient adsorption property for MB and Pb(II). POLYM. COMPOS., 39:1663–1673, 2018. © 2016 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

TiO 2 nanosheets (TNSs) with high percentage active facets (001) are anchored to three-dimensional RGO networks (3DGNs) followed by dipping into tetrabutyltitanate and calcinating under nitrogen atmosphere to prepare high loading of TNSs and TiO 2 nanoparticles (TiO 2 NPs) onto the 3DGNs composites (TNSs-TiO 2 NPs/3DGNs). The structure and morphology of the TNSs-TiO 2 NPs/3DGNs composites are characterized by Fourier transform infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD) and scanning electron microscopy (SEM). With TNSs and TiO 2 NPs on the surface of 3DGNs, the TNSs-TiO 2 NPs/3DGNs composites show high photocatalytic activity in the degradation of 4-nitrophenol (4-NP) owing to more catalytic sites, high light absorbing capacity, fast charge transportation and separation ability, and high adsorption ability for 4-NP. The results show that the removal efficiency of 4-NP over the TNSs-TiO 2 NPs/3DGNs is close to 72% after 75 min illumination, which is 8.34 times as much as that of TNSs, 2.70 times as much as that of TiO 2 NPs/3DGNs and 1.31 times as much as that of TNSs/3DGNs, respectively. [ABSTRACT FROM AUTHOR]

Hybrid nanocrystals of PVBA- b-PS/ZIF-8 were prepared by the growth of ZIF-8 on the surface of the self-assembled structures from poly( p-vinylbenzoic acid)-block-polystyrene. Two different morphologies-micelles and vesicles-were obtained in selective solvents owing to the different ratios of PVBA to PS blocks. The structure and morphology of the PVBA- b-PS/ZIF-8 composites were characterized by Fourier transform IR spectroscopy, thermogravimetric analysis, X-ray diffraction, transmission electron microscopy and scanning electron microscopy. PVBA- b-PS/ZIF-8 showed high catalytic performance in Knoevenagel condensation reactions at room temperature, which were attributed to the more exposed active sites of the small ZIF-8 nanocrystals grown in a confined space and a high concentration of reactants in the polymeric aggregates. [ABSTRACT FROM AUTHOR]

TiO 2 /graphene porous composites with reduced graphene oxide (rGO) as its inner surface were prepared based on graphene microspheres colloidal crystals template. The structure and morphology of TiO 2 /graphene porous composites were characterized by Fourier transform infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD) and scanning electron microscopy (SEM). With rGO sheets as the interface of the porous TiO 2 /graphene, the composites exhibited high light absorbing capacity, high adsorption ability for methylene blue (MB) and fast charge transportation and separation ability. TiO 2 /graphene porous composites showed superior activity in the degradation of MB under visible light. The rate constant of TiO 2 /graphene porous composite was 0.0208 min − 1 , which was almost 6.5 times higher than P25 under the visible-light-driven radiation. [ABSTRACT FROM AUTHOR]

Reduced graphene oxide/meso-TiO 2 /AuNPs (RGO/meso-TiO 2 /AuNPs) ternary composites were prepared via the addition of graphene oxide to the dispersion of meso-TiO 2 /AuNPs under hydrothermal conditions. The structure and the morphology of the RGO/meso-TiO 2 /AuNPs materials were characterized using X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), and scanning electron microscopy (SEM). The photocatalytic activity of RGO/meso-TiO 2 /AuNPs was evaluated by degradation of methyl blue (MB) under visible-light illumination. The ternary composites present an extended light absorption range, efficient charge separation properties, high adsorption ability for MB and high photocatalytic degradation activity of MB compared to the meso-TiO 2 and meso-TiO 2 /AuNPs. [ABSTRACT FROM AUTHOR]

Background: From 1973 to 2005, the lung cancer mortality in Xuanwei had increased constantly. Effect analysis of age and non-age factors on lung cancer is important for local policy-making.Methods: Demographic and death data was collected and used. Factors of lung cancer were classified into age and non-age factors. The contribution of the two factors to lung cancer was evaluated by method of decomposing the differences of mortality rate.Results: For males, the non-age factors were the major contributor to growth of lung cancer mortality, and 78.46% of all growth was attributed to non-age factors. For females, the non-age factors were the absolute contributor to growth of lung cancer in 1973-1992. From 1992 to 2005, the contribution proportion had reduced to 75.39%.Conclusions: Aging was one of risk factors for lung cancer in Xuanwei, but not the main factor. It was supposed that multiple environmental risk factors were related with high growth of lung cancer in Xuanwei. Policy-making should focus on the non-age factors. [ABSTRACT FROM AUTHOR]

Carboxylgroups at the periphery of reduced graphene oxide (RGO)sheets are converted to amine groups by reaction with N-hydroxysuccinimide and 1,3-diaminopropane, and a free-radical polymerizationinitiator is anchored to the RGO sheets. Poly(acrylamide) (PAM) polymerbrushes on RGO sheets (RGO/PAM) are synthesized by in situ free-radicalpolymerization. The heavy metals, Pb(II), and the benzenoid compounds,methylene blue, (MB) were selected and adsorbed by RGO/PAM composites,and the adsorption capacity of RGO/PAM for Pb(II) and MB was measured.The experimental data of RGO/PAM isotherms for Pb(II) and MB followedthe Langmuir isotherm model. The RGO/PAM displays adsorption capacitiesas high as 1000 and 1530 mg/g for Pb(II) and MB, respectively, indicatingRGO/PAM is a good adsorbent for the adsorption of Pb(II) and MB. Theadsorption kinetics of Pb(II) and MB onto RGO/PAM can be well fittedto the pseudo-second-order model. The adsorption processes of Pb(II)and MB onto RGO/PAM are spontaneous at 298, 308, and 318 K. [ABSTRACT FROM AUTHOR]

Preparation and characterization of poly( N-isopropylacrylamide) (PNIPAM) polymer brushes on the surfaces of reduced graphene oxide (RGO) sheets based on click chemistry and reversible addition-fragmentation chain transfer (RAFT) polymerization was reported. RGO sheets prepared by thermal reduction were modified by diazonium salt of propargyl p-aminobenzoate, and alkyne-functionalized RGO sheets were obtained. RAFT chain transfer agent (CTA) was grafted to the surfaces of RGO sheets by click reaction. PNIPAM on RGO sheets was prepared by RAFT polymerization. Fourier transform-infrared spectroscopy, thermogravimetric analysis, X-ray photoelectron spectroscopy, and transmission electron microscopy (TEM) results all demonstrated that RAFT CTA and PNIPAM were successfully produced on the surfaces of RGO sheets. Nanosized PNIPAM domains on RGO sheets were observed on TEM. Micro-DSC result indicated that in aqueous solution PNIPAM on RGO sheets presented a lower critical solution temperature at 33.2 °C. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012 [ABSTRACT FROM AUTHOR]

Porphyrinic covalent organic frameworks (COFs, specifically DhaTph) in the absence or presence of Cu2+ in porphyrin centers, were synthesized by a Schiff base condensation reaction of 5,10,15,20‐tetrakis(4‐aminophenyl)‐porphyrin (Tph) and 2,5‐dihydroxyterephthalaldehyde (Dha). Using 2,4,6‐trimethylbenzaldehyde (TBA) as a competition reagent, the hollow DhaTph Tubes and DhaTph‐Cu Tubes were obtained under solvothermal conditions. A detailed mechanism of formation of the tubular microstructure revealed the time‐dependent transformation into the tube via migration of the unstable central part of the initial solid rod. The DhaTph‐Cu Tubes possessed a high photoreduction efficiency of CO2 and the rate constants of CO and methane production are 15.9 and 13.7 μmol g−1 h−1 in the absence of any cocatalysts, which is about 3 and 7.6 times of DhaTph COF, respectively. The high effective photocatalytic reduction of CO2 activity of DhaTph‐Cu Tubes is attributed to the high specific surface area, strong absorption of visible light, and the fast separation and transferability of electrons and holes. This work not only provides in‐depth insights into the formation mechanism of the tubular COF but also reveals the relation between the morphology and the photocatalytic property based on COFs. [ABSTRACT FROM AUTHOR]

[Display omitted] • NiFe-LDH were grown vertically on the surface of BTO which provided more active sites. • t-BTO@NiFe-LDH has excellent OER property due to the self-polarized ferroelectric t-BTO. • Interface tension between BTO and NiFe-LDH made BTO easily self-polarize, causing band tilting. • The superior OER activity results from the active sites and the optimized d-band center. • The design of a ferroelectric OER electrocatalyst based on self-polarization is provided. A flower-like core–shell heterostructured oxygen evolution reaction (OER) electrocatalyst based on tetragonal BaTiO 3 nanoparticles (t-BTO NPs) and NiFe-layered double hydroxide (NiFe-LDH) nanoarrays was prepared in this study. The influence from the self-polarization effect of t-BTO on the OER performance of NiFe-LDH is reported. Intriguingly, the OER activity of the t-BTO@NiFe-LDH heterojunctions in an alkaline media (1.0 M KOH) exhibited a low overpotential of 186 mV at 10 mA/cm2 and a low Tafel slope of 38.3 mV dec-1, which were far superior to those of the component materials: NiFe-LDH (267 mV and 94.8 mV dec-1) and t-BTO NPs (517 mV and 132.4 mV dec-1). Density functional theory (DFT) calculations revealed that the effective electronic modulation between t-BTO NPs and NiFe-LDH nanoplatelets narrowed the bandgap, promoted the electric conductivity, moderately raised Ed (i.e., energy level of the d-band center), optimized the adsorption ability of the oxygen-containing intermediates (*O, *OH, and *OOH), and induced an apparent reduction in the free energy barrier for the transformation from O* to OOH* in the t-BTO@NiFe-LDH heterojunctions. The PDOS result confirmed that t-BTO in the heterojunctions was easier to polarize, which can cause the rapid electron transfer in the OER process. In these heterostructures, the interface tension between BTO NPs and NiFe-LDH endowed BTO with easier self-polarization, thus leading to greater band tilting and faster electron transfer. Multiple synergistic effects of the flower-like core–shell t-BTO@NiFe-LDH heterojunctions enabled them with higher electrocatalytic activity. This work provides an in-depth understanding of the rational design of a high-efficiency, noble metal-free ferroelectric OER electrocatalyst based on the self-polarization of t-BTO NPs. [ABSTRACT FROM AUTHOR]

[Display omitted] • A full-spectrum available photothermal S-scheme heterojunction is prepared. • Synergy of defects and IEF improves charge transport and separation efficiency. • The inverse opal structure with slow-light effect enhances light-capturing ability. • IO-B-TiO 2 /In 2 O 3 performs superior CO yield of 251.25 μmol·g−1·h−1. • DFT and experiments explored the reaction mechanism and S-scheme structure. The conversion of greenhouse gases such as carbon dioxide (CO 2) into fuel and high-value chemical materials using solar energy is considered as a viable solution to the environmental pollution and the alleviation of the energy crisis. Herein, a black titanium dioxide/indium oxide S-scheme heterojunction (IO-B-TiO 2 /In 2 O 3) with a three-dimensional porous inverse opal structure was prepared. In the photocatalytic reduction of CO 2 , IO-B-TiO 2 /In 2 O 3 exhibited an excellent CO production rate (251.25 μmol·g−1·h−1), being 8.62 and 1.55 times of pure IO-TiO 2 and IO-B-TiO 2 /In 2 O 3 under non-photothermal conditions, respectively. A series of characterizations and theoretical calculations (DFT) systematically demonstrated that the excellent photocatalytic performance results from the full spectral response of the material, fast charge separation and transport efficiency, and superior photothermal conversion efficiency of the infrared light. This work will provide a promising insight to the design of S-scheme catalysts with outstanding photocatalytic performance via photothermal assistance and the improved solar energy conversion efficiency. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Ni loaded inverse opal black TiO 2 were prepared by one-pot hydrothermal process. • IO-B-TiO 2 /Ni can be used as a high efficient photocatalysis for CO 2 reduction. • The formation rate of CO of IO-B-TiO 2 /Ni is about 10.1 times as high as that of P25. Abstract The photocatalytic reduction of CO 2 to high value organic substances using solar energy is significantly important to resolve both energy crisis and greenhouse effect. Thus so, Ni loaded inverse opal black TiO 2 (IO-B-TiO 2 /Ni) were successfully prepared. Combining slow photon effect of IO material, the faster charge transfer rates caused by the loading of Ni into TiO 2 with the hydrogenated disorder layer of the black TiO 2 for light harvesting and charge separation, the IO-B-TiO 2 /Ni can be used as a stable and highly efficiency catalyst for reduction of CO 2. The formation rate of CO of IO-B-TiO 2 /Ni is 12.1 μ·mol·g−1·h−1, which is about 10.1, 5.1 and 2.0 times as P25, IO-W-TiO 2 and IO-B-TiO 2 , respectively. [ABSTRACT FROM AUTHOR]

The reduced graphene oxide-poly-(2-(dimethylamino)ethyl methacrylate)-Pt/Ag (RGO-PDMAEMA-Pt/Ag) nanoscrolls were prepared by rolling up the RGO-PDMAEMA-Pt/Ag sheets under freezing conditions. The compositions and structures of RGO-PDMAEMA-Pt/Ag sheets and nanoscrolls were characterized by Fourier transform infrared (FTIR) spectroscopy, thermogravimetric analysis (TGA), scanning electronic microscopy (SEM) and transmission electron microscopy (TEM). Because of the bimetallic synergetic effect and unique scrolled structure, RGO-PDMAEMA-Pt/Ag nanoscrolls show excellent catalytic performance and high electrochemical stability. The ECSA value of RGO-PDMAEMA-Pt/Ag nanoscrolls for Pt is 891 cm 2 /mg, which is 1.28 times that of the RGO-PDMAEMA-Pt/Ag sheets (698 cm 2 /mg). The ratio of the forward oxidation peak current to the reverse peak current is about 1.25. The electrochemical results indicate the RGO-PDMAEMA-Pt/Ag nanoscrolls are promising electrocatalysts for direct methanol fuel cell. [ABSTRACT FROM AUTHOR]

An efficient catalyst for the direct hydroxylation of benzene to phenol with H 2 O 2 was prepared via the anchor of H 5 PMo 10 V 2 O 40 (PMoV 2 ) by OH of Titania nanotubes (TNT) via electrostatic interaction between the Keggin unit of PMoV 2 and OH. The results of Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), solid-state 31 P nuclear magnetic resonance (solid-state 31 P NMR), X-ray photoelectron spectroscopy (XPS) and thermo gravimetric analysis (TGA) demonstrated that PMoV 2 was successfully immobilized on the surface of Titania nanotubes by electrostatic interaction. The textural and morphology of PMoV 2 /Titania nanotubes were characterized by N 2 adsorption-desorption, scanning electronic micrograph (SEM) and transmission electron microscope (TEM). PMoV 2 /Titania nanotubes shows excellent catalytic performance in the hydroxylation of benzene with a 27.3% benzene conversion and 99.1% selectivity to phenol. The results of contact angle and adsorption experiments demonstrate that excellent catalytic performance is attributed to the confinement effect of Titania nanotubes with the nanotube structure and hydrophobic microenvironment, which effectively disperse PMoV 2 and concentrate the reactants as well as decrease intrinsic mass transfer resistance. The anchor effect of OH stabilizes and inhibits the leak of PMoV 2 , leading to good catalytic recyclability with almost unchanged catalytic efficiency after six recycling tests in the acid reaction condition. [ABSTRACT FROM AUTHOR]

The two-dimensional (2D) Zn-MOF-NH 2 /Cu heterojunctions were prepared via in situ photodeposition of Cu NPs on the surface of 2D Zn-MOF-NH 2. The 2D Zn-MOF-NH 2 /Cu (1 wt%) heterojunction exhibited the excellent photocatalytic activity with a CO production rate of 0.76 μmol/h under irradiation of full spectrum light only using H 2 O as a hole sacrificial agent, which is 16.2 and 2.7 times that of bulk Zn-MOF-NH 2 and 2D Zn-MOF-NH 2 nanosheets, respectively. This work provides an insight into design of a highly efficient 2D MOFs-based photocatalysts in catalytic CO 2 reduction. • 2D Zn-MOF-NH 2 nanosheets were prepared by a mild method. • 2D Zn-MOF-NH 2 /Cu heterojunctions have excellent activity in photocatalytic reduction of CO 2. • The CO generation rate of 2D Zn-MOF-NH 2 /Cu (1 wt%) is 16.2 times that of bulk Zn-MOF-NH 2. [ABSTRACT FROM AUTHOR]

• This study provides a simple and effective method for the preparation of piezoelectricity-enhanced BaTiO 3 /g-C 3 N 4 photocatalysts via combination of modulation of ferroelectric domain and construction of heterostructure. • The anBTO/g-C 3 N 4 heterojunction under ultrasonication showed a high photocatalytic efficiency of 0.0462 min−1 in the degradation of LVF, which was 9.2 times that of arBTO NPs without ultrasonication. • The significantly improved photocatalytic activity of the heterostructure with ultrasonication was attributed not only to the piezoelectric effect of BTO and the tightly bound interface, but also the synergistic effects, such as narrowing the bandgap, band-bending, and accelerated separation of the photo-generated excitons at the heterojunction interface and piezoelectric potential. Nanoscale heterojunctions of high dielectric constant piezoelectrics and optoelectronic semiconductors are attractive for photocatalytic degradation of hazardous organic compounds. In this work, such a nano-heterojunction was prepared by mixing of surface-carboxylated ferroelectric BaTiO 3 nanoparticles (BTO NPs) and protonated graphitic carbon nitride (g-C 3 N 4). Due to strong electrostatic interactions, intimate contact between BTO NPs and g-C 3 N 4 was achieved for efficient charge separation and transfer. Two piezoelectric BTO NPs were used to prepare the BaTiO 3 /g-C 3 N 4 heterojunctions: as-received BTO (arBTO) and 950 °C-annealed BTO (anBTO) with larger ferroelectric domains. Under ultrasonication, the photocatalytic degradation rate of levofloxacin by anBTO/g-C 3 N 4 heterojunctions were 0.0462 min−1, which were 9.2 times of arBTO and 3.6 times of those in the absence of ultrasonication. The underlying mechanism was attributed to the higher current density, the accelerated charge separation of photo-activated excitons, and the reduced charge recombination via a synergistic effect of heterostructures and the local piezo-potential generated by the ferroelectric BTO NPs. By combination of thermal annealing of arBTO to enlarge the ferroelectric domains and construction of heterostructures, a highly efficient photocatalyst could be obtained. This study provides us a simple yet effective method to achieve highly efficient photocatalysts using the piezoelectric effect of ferroelectric BTO NPs. [ABSTRACT FROM AUTHOR]