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Secondary Li−ion batteries have been paid attention to wide‐range applications of power source for the portable electronics, electric vehicle, and electric storage reservoir. Generally, lithium‐ion batteries are comprised of four components including anode, cathode, electrolyte and separator. Although separators do not take part in the electrochemical reactions in a lithium‐ion (Li−ion) battery, they conduct the critical functions of physically separating the positive and negative electrodes to prevent electrical short circuit while permitting the free flow of lithium ions through the liquid electrolyte that fill in their open porous structure. Hence, the separator is directly related to the safety and the power performance of the battery. Among a number of separators developed thus far, polyethylene (PE) and polypropylene (PP) porous membrane separators have been the most dominant ones for commercial Li−ion batteries over the decades because of their superior properties such as cost‐efficiency, good mechanical strength and pore structure, electrochemical stability, and thermal shutdown properties. However, there are main issues for vehicular storage, such as nonpolarity, low surface energy and poor thermal stability, although the polyolefin separators have proven dependable in portable applications. Hence, in this review, we decide to provide an overview of the types of polyolefin microporous separators utilized in Li−ion batteries and the methods employed to modify their surface in detail. The remarkable results demonstrate that extraordinary properties can be exhibited by mono‐ and multilayer polyolefin separators if they are modified using suitable methods and materials.

This review gives an overview of the synthesis, surface and electrochemical investigations over ternary nanocomposite of conductive polymers in the development of new supercapacitors. They utilize both Faradaic and non‐Faradaic procedures to store charge, leading to higher specific capacitance and energy density, higher cell voltage, longer life cycle and moderated power density. Owing to a unique combination of features such as superb electrical conductivity, corrosion resistance in aqueous electrolytes, highly modifiable nanostructures, long cycle life and the large theoretical specific‐surface area, the use of ternary nanocomposites as a supercapacitor electrode material has become the focus of a significant amount of current scientific researches in the field of energy storage devices. In these nanocomposites, graphene not only can be utilized to provide a substrate for growing nanostructured polymers in a polymer‐carbon nanocomposite structure in order to overcome the insulating nature of conductive polymers at dedoped states, but also is capable of providing a platform for the decoration of metal oxide nanoparticles to avoid their agglomeration. In this regard, synthesis, characterization and performance of different ternary nanocomposites of conductive polymer/graphene/metal oxide are discussed in detail. These remarkable results demonstrate the exciting commercial potential for high performance, environmentally friendly and low‐cost electrical energy storage devices based on ternary nanocomposite of conductive polymer/graphene/metal oxide.

A thin film composite (TFC) membrane with superior characteristics for organic solvent nanofiltration (OSN) was successfully prepared. Accordingly, a state-of-the-art polyethylene (PE) membrane support was first prepared through etching the polystyrene (PS)/styrene–ethylene–butylene–styrene (SEBS) phase, as the dispersed phase, from the fabricated PE/SEBS/PS composite using the solvent extraction technique. Different compositions were fabricated so that a suitable ultrafiltration membrane support could be achieved. Due to the high hydrophobicity of the prepared PE membrane support (Etched PE) and lack of polar functional groups on its surface, the impregnation with an m-phenylenediamine (MPD) aqueous solution and, consequently, the formation of the polyamide layer on the PE surface were restricted. Hence, the prepared PE membrane supports were immersed in potassium permanganate (KMnO4) solutions with different concentrations so that the PE surface could be oxidized, by which polar functional groups were generated and manganese­(IV) dioxide (MnO2) nanoparticles were also formed on the surface via a relatively strong bond. Next, MPD and trimesoyl chloride (TMC) monomers with different concentrations were utilized for the formation of a cross-linked TFC layer on the MnO2-loaded PE surface. The TFC membranes showed a hydrophilic and defect-free polyamide barrier layer, high separation performance (dye rejection as high as 99.8% for methyl green), methanol permeance of 7 L/m2·h, and high methanol permeance after dimethylformamide (DMF) activation (14 L/m2·h). Furthermore, a superior solvent resistance (dye rejections of more than 98.5, 97.0, 96.0, and 93.5% for methyl green, rhodamine B, crystal violet, and methylene blue, respectively, being immersed in DMF at 75 °C for about 100 days) was exhibited by the prepared membranes, which demonstrated their promising potential in the OSN applications.

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