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Acid‐alkaline amphoteric water electrolysis (AAA‐WE) can produce green hydrogen under reduced voltage and energy consumption. However, its conflicting demands on ion exchange membranes to have both high ionic conductivity and barrier properties between H+ and OH− have thwarted its own development. Here, the preparation of anisotropic polybenzimidazole (PBI) ion‐solvating membrane (ISM) made of hundreds of 28 nm thick nano‐sheets (PBI‐aNS) from gel state PBI (PBI‐Gel) membranes via 2D‐polarized/1D shrinking process, in which loosely packed multi‐layer PBI nano‐fibrous assemblies are shrunken into hundreds of layers of tight 28 nm thick nano‐sheets, is reported. The resulting PBI‐aNS membranes possess excellent dual‐ion conductivity (H+ and OH−), good acid/alkali barrier capability, and robust mechanical properties. Acid‐alkaline amphoteric water electrolysis (AAA‐WE) using PBI‐aNS separators achieves a high current density of 1 A cm−2 at 1.4 V (with iR‐correction) under a voltage increasing rate of 6.1 mV h−1. This newly designed ISM will lead to new possibilities for the development of next‐generation water electrolysis devices with improved green hydrogen production efficiencies. [ABSTRACT FROM AUTHOR]

Electrodialysis, an efficient and environmental friendly separation technology, plays a significant role in water treatment. In order to reveal ion transfer mechanism and predict electrodialysis behavior, a mathematical model for steady transport of a binary electrolyte during the desalination process was developed. The Nernst–Planck, electroneutrality equations, and other hydrodynamic equations were coupled and solved with appropriate boundary conditions using the finite element method. This model is capable to predict the local ion concentration, electric potential, and ion flux in a rectangular electrodialysis unit. The effects of voltage drop (0.4–1.0 V), inlet velocity (0.03–0.06 m/s), and initial feed concentration (500–700 mol/m3) are investigated, which could provide valuable guidance for electrodialysis operation in the practical project. Moreover, this model is validated by comparing its simulation result with experimental data of electrodialysis, and it could predict the desalination of saline water accurately. Ion transfer modeling provides an effective way to study the transfer mechanism, estimate the effects of various parameters conveniently, and realize the target‐oriented operation optimization. [ABSTRACT FROM AUTHOR]

The aim of this work has been to study the influence of modified hole-extraction layers on the performance of organic solar cells (OSCs) based on blends of poly (3-hexylthiophene) and [6,6]-phenyl-C61-butyric acid methyl ester. The hole-extraction layers consist of poly (3,4-ethylene dioxythiophene):polystyrene sulfonic acid (PEDOT:PSS) doped with different concentrations of bromine. Compared with pristine OSC without adding bromine to the hole-extraction layer, the bromine-doped OSCs show a 49% increase in the power conversion efficiency (from 2.12 to 3.16%), which could be attributed to the increase of electrical and optical properties of PEDOT:PSS films after the addition of bromine. © 2011 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 50: 125-128, 2012 [ABSTRACT FROM AUTHOR]

A bench-scale submerged membrane bioreactor (SMBR) was employed to treat vegetable oil plant wastewater with complete sludge retention. Treatment performance and membrane fouling of the SMBR were investigated. The system stably removed high amounts of total organic carbon, oil, and ammonia from vegetable oil wastewater and reduced the chemical oxygen demand, demonstrating the great potential of the SMBR in removing pollutants. The membrane fouling layer was not only governed by deposition of organic substances composed of extracellular polymeric substances like proteins, polysaccharides etc., and oil substances but also by inorganic elements. Organic foulants coupled to inorganic precipitation enhanced the formation of a gel layer and triggered severe membrane fouling in the SMBR. [ABSTRACT FROM AUTHOR]