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• 1. The PH/CS layer was constructed on the membrane surface by incorporating CS nanoparticles. • 2. PH/CS layer with beads-on-string structure reduced temperature polarization in MD membrane. • 3. The water flux of ENMs was increased 2.4 times after incorporating CS in PH nanofiber. • 4. PH/CS composite ENMs exhibited good long-term stability of over 5100 min. Membrane distillation (MD) is a promising technology among various desalination processes. However, the membrane used in MD is still problematic due to its low permeability and tendency to become wet. In this work, we fabricated a novel electrospun nanofiber membrane (ENM) with micro-nano structures resembling beads on a string to enhance water flux and anti-wetting properties in MD desalination. The composite ENM consists of a heat-conducting top layer made of polyvinylidene fluoride co-hexafluoropropylene (PH) nanofibers embedded with carbon sphere (CS) nanoparticles and a heat-insulating support layer made of pH nanofibers. The PH/CS top layer with beads-on-string micro-nano structures can not only provide a rough surface to elevate anti-wetting property of the membrane, but also create a maximum temperature difference inside the membrane to improve mass transfer of water vapor. The PH/CS composite ENMs acquired the highest water flux of ∼ 71.3 L m−2 h−1 at a temperature difference of 40 °C, and its salt rejection rate for a 3.5 wt% NaCl solution was higher than 99.9% in direct contact membrane distillation. Meanwhile, the composite ENM exhibited long-term stability of 5100 min. Our work presents a novel composite ENM with great potential for promoting water flux and anti-wetting properties towards MD desalination. [ABSTRACT FROM AUTHOR]

Graphical abstract Ag-AgBr microspheres were deposited on the surface of TiO 2 nanotube arrays by a solvothermal method. The visible light photocurrent density of TiO 2 NTs/Ag-AgBr (SH) was 5.86 mA/cm2, the photovoltage was −0.31 V/cm2, the flat band was −0.79 V, and the carrier concentration was 1.77 × 1020 cm−3. The TiO 2 NTs/Ag-AgBr (SH) showed the optimal photoelectrocatalytic removal efficiencies of methyl orange, rhodamine B, methyl blue and Cr(VI). Highlights • Ag-AgBr nanospheres were deposited on TiO 2 nanotube arrays by a hydrothermal method. • The TiO 2 NTs/Ag-AgBr (SH) photoelectrode showed the excellent photoelectrochemical properties. • The PEC mechanism of TiO 2 NTs/Ag-AgBr photocatalysts was proposed. Abstract The TiO 2 nanotube arrays (TiO 2 NTs) sensitized by Ag-AgBr nanoparticles were prepared with different alkali (sodium hydroxide, urea and methenamine) as mineralizers by a hydrothermal method, and the TiO 2 NTs/Ag-AgBr photoelectrode showed high visible light absorption, transient photocurrent and photoelectrocatalytic (PEC) performances. The results indicated that TiO 2 NTs/Ag-AgBr (SH) photoelectrode showed the high visible light photocurrent density of 5.86 mA/cm2, photovoltage of −0.31 V/cm2 and PEC removal efficiency for MO (71.97%), RhB (59.88%), MB (80.76%) and Cr(VI) (52.24%), respectively. The high PEC property could be attributed to the high activities of solar absorption and electron separation. The excellent photoelectrochemical property of TiO 2 NTs/Ag-AgBr would induce the novel photoelectrode promising applications in solar cells and wastewater treatment. [ABSTRACT FROM AUTHOR]

Graphical abstract CuO nanosheets were deposited on the surface of TiO 2 nanotube arrays by a SILAR method. The visible light photocurrent density of TiO 2 NTs/CuO (M) was 19.81 mA/cm2, the photovoltage was −0.59 V/cm2, the flat band was −0.53 V, and the carrier concentration was 5.57 × 1019 cm−3. The TiO 2 NTs/CuO (M) showed the optimal photoelectrocatalytic removal efficiencies of methyl orange, rhodamine B, methyl blue and Cr(VI). Highlights • CuO nanosheets were deposited on TiO 2 nanotube arrays by a SILAR method. • The TiO 2 NTs/CuO (M) photoelectrode showed the excellent photoelectrochemical properties. • The PEC mechanism of TiO 2 NTs/CuO photocatalysts was proposed. Abstract The CuO nanosheets were deposited on the surface of TiO 2 nanotube arrays (TiO 2 NTs/CuO) by the successive ionic layer adsorption and reaction (SILAR) method at 90 °C. The results indicated that the reactant concentration influenced the morphology, visible light response and corresponding photoelectrochemical performances of TiO 2 NTs/CuO. The TiO 2 NTs/CuO (M) prepared in 0.04 mol/L of Cu2+ solution possessed the highest visible light photocurrent (19.81 mA/cm2), photovoltage (−0.59 V/cm2) and charge carrier concentration (5.57 × 1019 cm−3) among these photoelectrodes. Beside, the TiO 2 NTs/CuO (M) photoelectrode could achieve rapid pollutant removal, and the photoelectrocatalytic (PEC) efficiencies for RhB, MO, MB and Cr(VI) were 55.36%, 48.28%, 89.61% and 74.76% under solar irradiation, respectively. Hence, the novel TiO 2 NTs/CuO (M) photoelectrode would exhibit excellent property in the applications of solar cells and photocatalysts. [ABSTRACT FROM AUTHOR]

Graphical abstract The 3D TiO 2 nanotube arrays (TiO 2 NTs) were prepared by the anodization of Ti meshes via adjusting the anodization voltage. The solar photocurrent density of TiO 2 NTs (30) was 1.63 mA/cm2 and the photovoltage was −0.36 V/cm2. The TiO 2 NTs (30) showed the optimal photoelectrocatalytic removal efficiencies of methyl orange, rhodamine B, methyl blue and Cr(VI). Highlights • TiO 2 nanotube arrays on Ti mesh were prepared by the anodization method. • The TiO 2 NTs (30) photoelectrode showed the excellent photoelectrochemical properties. • The PEC mechanism of TiO 2 NTs photocatalysts was proposed. Abstract The 3D TiO 2 nanotube arrays (TiO 2 NTs) were prepared by the anodization of Ti meshes via adjusting the anodization voltage. The anodization voltage between 15 and 60 V could form the uniform tubular structures revolving around Ti wires, and the diameter and length increased with the increasement of voltages. The results indicated that the anatase TiO 2 NTs (30) prepared with the andization voltage of 30 V showed excellent solar photocurrent, photovoltage, interface impedance and photoelectrocatalytic (PEC) efficiencies for the removal of dye molecules and Cr(VI) heavy metal ions. The TiO 2 NTs (30) sample with the average diameter of 70 nm and thickness of 4.56 μm showed photocurrent density of 1.63 mA/cm2, photovoltage of −0.36 V/cm2 and removal efficiencies of 71.31%, 51.39%, 98.07% and 48.26% for the PEC removal of methyl orange (MO), Rhodamine B (RhB), methyl blue (MB) and Cr(VI), respectively. The excellent photoelectrochemical propery of TiO 2 NTs (30) could be attributed to the effective pollutant adsorption and carrier transportation. This flexible photoelectrode would cause intense attention in the applications of solar cells, pollutant degradation, photolysis of water, and gas sensor. [ABSTRACT FROM AUTHOR]

[Display omitted] • Mussel-inspired graphene oxide-polydopamine-lysine nanosheets was synthesized. • This biomimetic GO nanosheets were more evenly dispersed in the membrane. • The membrane shows high water permeability (850 L m−2·h−1 bar−1) and BSA rejection. • The MMMs with GO-bsaed nanosheets exhibits excellent antifouling and bactericidal properties. A multi-functional bio-inspired graphene oxide (GO) nanosheet was prepared firstly by successively modifying GO nanosheets with polydopamine (GO-PDA) and lysine (GO-PDA-LYS). Subsequently, the modified GO-blended polyvinylidene fluoride (PVDF) (PVDF/(GO-PDA-LYS)) MMMs were fabricated via non-solvent induced phase separation (NIPS) method. The presence of biomimetic GO-based nanosheets with good compatibility further improves the hydrophilicity of MMMs and endows them with favorable antifouling and antibacterial properties. The resultant MMMs show a competitive rejection rate (95.2%) of bovine serum albumin (BSA) and high pure water permeability of 850 L m-2h−1 bar−1, which is 7 times higher than that of the original PVDF membrane, as well as a high flux recovery ratio of over 80%. Moreover, the results of the Raman spectroscopy demonstrate that GO-PDA-LYS nanosheets are more evenly dispersed on the membrane surface than GO or GO-PDA nanosheets due to their better compatibility, thereby further improving antifouling and antibacterial performance of MMMs. This multi-functional biomimetic GO-PDA-LYS nanosheet provides new insights into an effective strategy for synchronously enhancing the water permeability, antifouling and antibacterial performance of MMMs. [ABSTRACT FROM AUTHOR]

Abstract: A microwave-assisted extraction (MAE) method was developed for simultaneous extraction of hydrosoluble phenolic acids and liposoluble tanshinones in Salviae Miltiorrhizae radix. The key parameters considered for the MAE included solvent type, temperature, microwave power, solvent to material ratio and extraction time. Multiple response optimization based on desirability functions was used to optimize MAE process. Simultaneous extraction of the hydrosoluble and liposoluble components was demonstrated to be feasible by MAE. Selecting of solvent was the first important factor. The mixed solvent of methanol and water (80:20, v/v) was the most suitable extractant. The optimized parameters of MAE were: employing 80% methanol as solvent, microwave power 800W, temperature 70°C, ratio of liquid/solid 35mL/g and extraction time 7.5min. Compared to conventional extraction methods, the developed MAE showed the highest extraction yield within the shortest time and the advantage of preventing degradation of components. The results showed an improved method for simultaneous extraction of hydrosoluble and liposoluble components. [Copyright &y& Elsevier]