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To form a conducting network at a low temperature in printed electronic circuits, conductive metal fillers for e-inks have to be small in size because the melting point of a nanoparticle (NP) is inversely correlated with its radius. We prepared NP using a one-step synthesis process with direct ligand exchange and the nano-materials showed metallization at low temperatures. TEM images showed that the final spherical particles have diameters of 5.4 ± 0.7 nm. The metallization of the silver NP was confirmed with SEM images and the metallization mechanism is discussed in detail. The results indicated that sinterization necks appeared with heat-treatment below 200 °C. [ABSTRACT FROM AUTHOR]

In our previous work, we demonstrated ion selective transport through a single membrane. In this study, we adopted a new method by using a dual membrane system to improve the performance. Two gold-sputtered membranes were mounted between two independent glass cells. Then, polypyrrole (PPy) was electrochemically deposited on the gold side of each membrane. Benzylamine (BA) and Methylene blue (MB) were used as the probe materials in this membrane system. Since the PPy serves as a separator and an electrode, an electric field could be applied between the two membranes directly. Furthermore, a high electric field could be obtained between the two membranes even at a low applied potential because the distance between the two membranes is in microunits. As a result, the dual membrane system exhibited improved control and selectivity for the ions. Finally, the different transport mechanism for BA and MB was discussed in detail. [ABSTRACT FROM AUTHOR]

A number of ion separation methods successfully separate ions by controlling the ion's transport. In general, transport rate of ions depends on their charge, size or hydrated radii. However, methylene blue (MB) used in this study showed different transport tendency compared to other ions. The results indicate that the transport of MB is affected by its adsorption property. Thus, we tried to elucidate the special transport mechanism of MB in detail. The conducting polymer modified membrane used in this study was prepared by the electrochemical polymerization of pyrrole on a gold-sputtered polycarbonate (PC) membrane in aqueous solution. Characterization of the polypyrrole (PPy) modified membrane was performed by scanning electron microscopy (SEM) and energy dispersive x-ray spectroscopy (EDX). The transport of MB through the PPy membrane was controlled by applied potentials. The concentration change of MB in permeated cell was detected by high performance liquid chromatography (HPLC) equipped with a UV-Vis detector. [ABSTRACT FROM AUTHOR]

It is well established that mixture of inorganic ions including heavy metals can be simply separated into components by using a conducting polymer membrane (CPM) system because each component has a unique charge or size of hydrated radius. However, studies about organic ion separations with the CPM system were hardly found even though organic ions are used in so many fields. Unlike inorganic ions, organic ions usually have complex characters can cause some specific interactions with the membrane and the specific interactions can affect their transport. However, in the case that the specific interactions are weak enough, the organic ion transport may be similar to that of inorganic ions. Thus, investigation of the organic ion transport should be done case by case. In this study, we investigated the transport phenomenon of an organic ion which has weak specific interactions with the membrane under different applied potentials and demonstrated its transport mechanism in detail. Benzylamine (BA) was chosen as the transporting ion and the experimental results showed that its transport was similar to that of inorganic ions even though it has different characters with them. In addition, we compared the transport property of BA to that of methylene blue (MB) which has a strong specific interaction with the membrane under same applied potential and suggested a possibility that organic ions could be separated based on the membrane selectivity. [ABSTRACT FROM AUTHOR]

Highly porous off-stoichiometric tungsten trioxide (WO 3-σ ) with hollow and yolk-shell structures have been successfully synthesized via a selective leaching strategy, following hydrogenation using PbWO 4 spheres as the starting material. It was found that the yolk-shell WO 3-σ could be obtained from hollow WO 3-σ by dividing the continuous leaching process into two intervallic processes. The unique structural features and high conductivity facilitate both ion and electron transport, greatly enhancing reversible lithium storage capacity. In comparisons of the hollow WO 3-σ and yolk-shell WO 3-σ , the yolk-shell structure exhibited more long-term stability due to extra spatial elasticity. [ABSTRACT FROM AUTHOR]

In this paper, we report on the ortho-hexaclaval and size-controlled spherical PbWO4 micro- and mesocrystals synthesized by the surfactant-assisted solvothermal method with cationic surfactant cetyltrimethylammonium bromide (CTAB), deionized water or ethylene glycol solvents. The resulting hierarchical PbWO4 crystals were characterized by X-ray diffraction, field emission scanning electron microscopy, high-resolution transmission electron microscopy and selected area electron diffraction. Experimental results indicated that CTAB played a critical role in the formation of specific structures. Finally, the optical properties were investigated at room temperature by means of ultraviolet-visible diffuse reflectance and photoluminescence measurements. [ABSTRACT FROM AUTHOR]