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We report a one-pot preparation method for a series of novel shaped gold microcrystals by simply mixing HAuCl4 with disodium salt of ethylenediaminetetraacetic acid (Na2EDTA). Under the different reaction temperatures, spinous structures, multipod microspheres, and rough surfaced microspheres were obtained. These microcrystals exhibit high surface-enhanced Raman scattering (SERS) activity.

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The anchoring of small-sized WN (tungsten nitride) nanoparticles (NPs) with good dispersion on carbon nanotubes (CNTs) offers an effective means of obtaining promising materials for use in electrocatalysis. Herein, an effective method based on grinding treatment followed by a nitridation process is proposed to realize this goal. In the synthesis, a solution containing H4 [SiO4 (W3 O9 )4 ] (SiW12 ) and CNTs modified with polyethylenimine (PEI-CNTs) was ground to dryness. Small-sized WN NPs were anchored onto the CNTs with good dispersion after calcination under NH3 . Under hydrothermal assembly conditions (absence of grinding), WN particles of larger size and with inferior dispersion were obtained, demonstrating the important role of the grinding process. The benefit of the small-sized WN has been demonstrated by using WN/CNTs as a support for Pt to catalyze the methanol electro-oxidation reaction. The mass activity of Pt-WN/CNTs-G-70 (where G denotes the grinding treatment, and 70 is the loading amount (%) of WN in the WN/CNTs) was evaluated as about 817 mA mg(-1) Pt , better that those of commercial Pt/C (340 mA mg(-1) Pt ) and Pt/CNTs (162 mA mg(-1) Pt ). The Pt-WN/CNTs-G also displayed good CO tolerance. In contrast, Pt-WN/CNTs prepared without the grinding process displayed an activity of 344 mA mg(-1) Pt , verifying the key role of grinding treatment in the preparation of WN/CNTs with good co-catalytic effect.

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In this article, a novel method of applying high voltage (1-5 kV) to the conventional immersion precipitation phase inversion process was used to prepare polyethersulfone ultrafiltration membranes when PVP (30 K) was used as an additive. The effects of the external electric field on the structure, surface functional groups, membrane potential, and surface hydrophilicity of the membranes were researched. Bovine serum albumin (BSA) adsorption amounts on the membranes and the separation performances of the membranes were measured. It was found that the external electric field influenced the surface carbonyl groups, surface hydrophilicity, and potential of the membranes. With the increase of the external voltage, the surface hydrophilicity and the membrane potential decreased. It seemed that the external voltage had no influence on the cross-section structure of the membranes, but the surface porosity density slightly reduced when the external voltage increased. In basic BSA solution, the protein adsorption amount on the electric enhanced membranes was distinctly reduced when compared with an un-enhanced membrane, and the rejection was also improved. Consequently, the prepared electric enhanced PES membranes had distinctive anti-fouling properties.