Zein nanofibrous membranes for sustained release have been prepared by coaxial electrospinning. Core-sheath structure has been successfully fabricated using zein as both the core and sheath component. Impact of solvent and solution concentration on the morphology of the resulting fibers was investigated. Allyltriphenylphosphonium bromide was used as a model drug to test the sustained release effect. The sustained release profile and the antimicrobial activity of the resulting membranes were investigated and compared with that of the single fluid electrospinning of zein/drug blended membrane. The ratio of the inner and outer feeding rates was found to influence the encapsulation of drugs, and in turn affect the sustained release effect of the resulting membranes. The coaxial electrospinning membrane can remarkably suppress the initial burst release of drugs by giving a releasing amount of 15% in the first 1 h when the inner/outer ratio was larger than 1:2. This drug-loaded zein membrane with preferable sustained release effect can be applied in many fields such as wound healing and packaging sector.

electrocatalyst for methanol oxidation reactions (MORs), has been considerably investigated. [2] However, toxic intermediate products such as CO produced in the catalytic oxidation process are easily adsorbed on the surface of Pt catalysts, leading to decreased electrocatalytic activity and low stability. Additionally, the high cost and scarcity of Pt heavily impede its widespread application. [3] To enhance the utilization efficiency and catalytic capability of Pt, other metals, such as Ag, [4] Pd, [5] Ni, [6] Cu, [7] and Au, [8] have been incorporated into Pt nanoparticles (NPs) to form bimetallic nanostructures by constructing core-shell or alloy nanostructures. In particular, Au NPs can effectively adsorb and activate surface oxygen species and promote the interaction between active oxygen and CO-like intermediates, thus increasing the stability of catalysts during the catalytic oxidation reaction. [8a,b] Consequently, Au-Pt bimetallic nanostructures are supposed to possess excellent synergistic catalytic effects for the MOR. [9] Recently, Au@Pt core-shell bimetallic nanostructures composed of an Au inner core and a thin Pt outer shell have become highly attractive for MORs because of the advantages of synergistic effects between Au and Pt, large surface areas, and high stability, resulting in a higher Pt utilization rate and catalytic performance. [10] However, most Au@Pt coreshell NPs are usually synthesized through solvothermal,

Recently, direct formic acid fuel cells (DFAFCs) which possess superior advantages such as a low operating temperature, light environmental pollution and high energy density, have been considered as one of the power generation technologies with a bright prospect. Herein, bimetallic PdAg nanoparticles (NPs) with different particle sizes were successfully produced via an easy one‐pot solvothermal co‐reduction synthetic route and their electrocatalytic performance for formic acid oxidation (FAO) were further investigated. In our strategy, the size of PdAg NPs can be easily controlled by only varying the concentration of precursors. The larger sized PdAg alloy (9.5 nm, noted as PdAg−L) was obtained at a low concentration of precursors, while the smaller PdAg alloy (3.7 nm, named as PdAg−S) was separated from the reaction system with higher solubility by centrifugation. The electrocatalytic activity and stability of the obtained PdAg NPs could be well optimized when incorporated with carbon (C), which is owing to a synergetic effect. The PdAg−S/C exhibits the highest mass activity with around 1.6 times that of PdAg−L/C and 2 times that of commercial Pd/C, which can be attributed to its larger ECSA and lower adsorption energy of the intermediate to facilitate the direct oxidation of HCOOH molecule.

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In order to enhance the hydrogen absorption performance and poisoning resistance of ZrCo to O2, Pd/ZrCo composite films were prepared by direct current magnetron sputtering. The results show that the initial hydrogen absorption rate of the Pd/ZrCo composite film increased significantly due to the catalytic effect of Pd compared with the ZrCo film. In addition, the hydrogen absorption properties of Pd/ZrCo and ZrCo were tested in poisoned hydrogen mixed with 1000 ppm O2 at 10–300 °C, where the Pd/ZrCo films maintained a better resistance to O2 poisoning below 100 °C. The mechanism of poisoning was investigated jointly by first-principles calculation combined with SEM-EDS elemental mapping tests. It is shown that the poisoned Pd layer maintained the ability to promote the decomposition of H2 into hydrogen atoms and their rapid transfer to ZrCo.