Nonprecious‐metal‐based electrocatalysts with low cost, high activity, and stability are considered as one of the most promising alternatives to Pt‐based catalysts for the oxygen reduction reaction (ORR). Herein, an economical and easy‐to‐fabricate catalyst is developed, that is, Fe/Fe3C embedded in N‐doped hollow carbon spheres (Fe/Fe3C/NHCS), which gave the half‐wave potential of 0.84 V in 0.1 m KOH, similar to the commercial Pt/C catalyst. Surprisingly, the favorable ORR performance of the as‐prepared catalyst was obtained in both acidic and neutral conditions with almost a four‐electron pathway and low H2O2 yield, which desirable the development of the proton exchange membrane (PEM) and microbial electrolysis cell (MEC) technology. Additionally, the obtained catalyst demonstrated better long‐term stability and high methanol tolerance over a wide range of pH. These features could be mainly attributed to the synergistic effect between Fe/Fe3C and Fe‐Nx sites, the hollow structure with mesopores, and the well‐dispersed Fe/Fe3C nanoparticles owing to the existence of the abundant hydrophilic groups within the HCS precursor. As such, designing an efficient and cheap ORR catalyst that can operate at alkaline, acidic, and neutral solutions is highly desirable, yet challenging.

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Anthocyanins microcapsules from Acanthopanax.sessiliflorus (Rupr. et Maxim.) Seem were prepared by Spray-Drying, using maltodextrin and gum arabic as wall materials. The stability and releasing property of anthocyanins microcapsules were studied. Using the retention rate as evaluation index, the effects of temperature, light, pH and metal ions on the stability of microcapsules and anthocyanins during 30 days storage were assessed, and samples were taken every five days. Results show that the microcapsules have greater storage stability against temperature, light, pH and metal ions. Using the release rate as evaluation index, the effect of releasing of microcapsules was evaluated, and samples were taken every 30min. Results show that the microcapsules have certain slow-release effect.

Eu3+-doped REVO4 nanphosphors were controllably synthesized by an EDTA-mediated hydrothermal method at 180 degrees C using RE(NO3)3 and Na3VO4 as precursors. The obtained products were characterized by X-ray powder diffraction (XRD), scanning electron microscopy (SEM), Fourier transform infrared spectrometry (FTIR), X-ray photoelectron spectra (XPS), and photoluminescence spectroscopy (PL). The XRD results showed that the products were pure tetragonal structure and no other impurity phase appeared. The PL studies demonstrated Eu3+ ions doping effectively enhanced luminescent properties of LaxRE(1-x)VO4 and YxRE(1-x)VO4 nanoparticles, but EU3+ ions doping did not enhance luminescent properties of CexRE(1-x)VO4 (x not equal 0) nanoparticles. The prepared phosphors showed well-defined red luminescence due to radiative transitions from 5D0 to 7F(J) (J = 1,2) levels of Eu3+ ions, respectively. Furthermore, we reported Eu3+-doped CexRE(1-x)VO4 (x not equal 0) phases represented a new class of optically inactive materials.