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Organic polymer electrolytes attracted a great deal of attention and research in the field of energy conversion and energy storage due to their benefits such as appreciable ionic conductivity and transference number, improved mechanical strength, thermal stability, and better interaction with the electrodes. In this study, a polymer electrolyte was synthesized from poly­(vinyl alcohol) (PVA) by electrospinning technique followed by soaking in a series of deep eutectic solvents (DESs) to enhance the electrical conductivity of the product. The result was a very thin, nonwoven membrane. The produced membranes showed appreciable improvement in electrical conductivity from 2.78 × 10–6 to 2.27 × 10–2 S/cm after soaking in DES2. The observed improvement in electrical properties opens the possibility for the PVA membranes to find their applications in batteries, storage cells, flexible thermoelectric devices, sensors, and solar cells.

Recently, a few studies have shown that the introduction of liquid crystals (LCs) in polymer electrolytes would lead to an increase in the chain mobility and the ionic conductivity. It is believed that this enhancement of the polymer electrolyte performance is greatly influenced by the order parameter of the liquid crystal in this system. In this study, a deuterated 4-pentyl-4-cyano-biphenyl (5CB-d2) nematic liquid crystal-doped polyvinyl alcohol (PVA) polymer electrolyte were prepared. The orientational order of the nematic liquid crystal is then investigated via the quadrupolar splittings of the deuterium Nuclear Magnetic Resonance (NMR) spectra. The quadrapolar splitting, which is directly related to the orientational order of the liquid crystal director, was measured and compared between the embedded 5CB-d2 in the PVA electrolyte to that of the pure 5CB-d2. The conductivity of a 5CB-d2 embedded in PVA reached up to 3.28x10-1 S/cm compare to that of without 5CB-d2 which is only 2.89x10-1S/cm. The presence of 5CB-d2 in the PVA polymer electrolyte improved the electrical conductivity of the mixture through an improved charge transfer mechanism, which improves its electrical properties, a criterion useful for a device that needs high conductivity.

No abstract

E-waste comprises discarded low quality protected electronic appliances that annually accumulate a million tons of hazardous materials in the environment.

<div class="page" title="Page 1"><div class="layoutArea"><div class="column"><p><span>Quaternary chalcogenide Cu</span><span>2</span><span>ZnSnS</span><span>4 </span><span>is a potential candidate for thermoelectric (TE) application due to a number of advantages including containing only non-toxic and abundant elements, high Seebeck coefficient and low thermal conductivity. In this study, Cu</span><span>2</span><span>ZnSnS</span><span>4 </span><span>was synthesized using mechanical alloying method from Cu, Zn, Sn and S powders. In order to study the effect of milling duration on the formation of Cu</span><span>2</span><span>ZnSnS</span><span>4</span><span>, different milling duration of 2, 4, 12 and 16 h were carried out. As the results, Cu</span><span>2</span><span>ZnSnS</span><span>4 </span><span>wasstarted to form after milling for 12 h. The formation of Cu</span><span>2</span><span>ZnSnS</span><span>4 </span><span>was completed after 16 h of milling. In addition, Cu</span><span>2</span><span>ZnSnS</span><span>4 </span><span>nanoparticles were obtained after 16 h of milling with the particle distribution mostly in the range of 50 - 60 nm. </span></p></div></div></div>

No abstract

Abstract-This paper proposes a copper nanoparticle ink printed frequency selective surface (FSS) for cellular signals suppression. The FSS pattern is deposited on a polyimide film by using an inkjet printing technique. The printed FSS elements undergo the post-processing called sintering, where the optimum exposure duration and temperature are determined in order to form a conductive path across the metal pattern. Later, the conductivity of the printed FSS structure deposited on polyimide film is observed. The signal suppression ability of the printed FSS is conducted using the Computer Simulation Technology (CST) Microwave Studio software.