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Developing low-cost and high efficient electrocatalysts for both oxygen and hydrogen evolution reaction in an alkaline electrolyte toward overall water splitting is still a significant challenge. Here, a novel hierarchically heterostructured catalyst composed of ultrasmall Mo 2 C and metallic Co nanoparticles confined within a carbon layer is produced by a facile phase separation strategy. During thermal reduction of CoMoO 4 nanosheets in CO ambient, in-situ generated nanoscale Co and ultrafine Mo 2 C conformally encapsulated in a conductive carbon layer. In addition, some carbon nanotubes catalyzed by Co nanoparticles vertically grew on its surface, creating 3D interconnected electron channels. More importantly, the integrated C@Mo 2 C/Co nanosheets assembled into the hierarchical architecture, providing abundant active surface and retaining the structural integrity. Benefiting from such unique structure, the constructed hierarchical heterostructure shows low overpotentials of 280 mV and 145 mV to reach a current density of 10 mA cm−2 for OER and HER in an alkaline electrolyte. Furthermore, the symmetrical electrolyzer assembled with catalyst exhibits a small cell voltage of 1.67 V at 10 mA cm−2 in addition to outstanding durability, demonstrating the great potential as a high efficient bifunctional electrocatalyst for overall water splitting. Image 1 • A novel hierarchically hetestructured C@Mo 2 C/Co electrocatalyst is constructed. • Ultrafine Mo 2 C and Co nanoparticles are conformally embedded in carbon matrix. • The carbon matrix acts as conductive substrate and structure support. • The C@Mo 2 C/Co electrocatalyst shows superior HER and OER performance in 1M KOH. • The C@Mo 2 C/Co presents bifunctionality of 1.67 V at 10 mA cm-2 for water splitting. [ABSTRACT FROM AUTHOR]

α-MnO 2 nanotubes and their supported Au-Pd alloy nanocatalysts were prepared using hydrothermal and polyvinyl alcohol-protected reduction methods, respectively. Their catalytic activity for the oxidation of toluene/ m -xylene, acetone/ethyl acetate, acetone/ m -xylene and ethyl acetate/ m -xylene mixtures was evaluated. It was found that the interaction between Au-Pd alloy nanoparticles and α-MnO 2 nanotubes significantly improved the reactivity of lattice oxygen, and the 0.91 wt.% Au 0.48 Pd/α-MnO 2 nanotube catalyst outperformed the α-MnO 2 nanotube catalyst in the oxidation of toluene, m -xylene, ethyl acetate and acetone. Over the 0.91 wt.% Au 0.48 Pd/α-MnO 2 nanotube catalyst, (i) toluene oxidation was greatly inhibited in the toluene/ m -xylene mixture, while m -xylene oxidation was not influenced; (ii) acetone and ethyl acetate oxidation suffered a minor impact in the acetone/ethyl acetate mixture; and (iii) m -xylene oxidation was enhanced whereas the oxidation of the oxygenated VOCs (volatile organic compounds) was suppressed in the acetone/ m -xylene or ethyl acetate/ m -xylene mixtures. The competitive adsorption of these typical VOCs on the catalyst surface induced an inhibitive effect on their oxidation, and increasing the temperature favored the oxidation of the VOCs. The mixed VOCs could be completely oxidized into CO 2 and H 2 O below 320°C at a space velocity of 40,000 mL/(g·hr). The 0.91 wt.% Au 0.48 Pd/α-MnO 2 nanotube catalyst exhibited high catalytic stability as well as good tolerance to water vapor and CO 2 in the oxidation of the VOC mixtures. Thus, the α-MnO 2 nanotube-supported noble metal alloy catalysts hold promise for the efficient elimination of VOC mixtures. [ABSTRACT FROM AUTHOR]

Abstract: Recently, the preparation of nanographitic materials have become one of the most active research fields, especially after the rise of graphene. Crystalline graphitic nanosheets have been prepared on the copper substrates by the energetic-beam deposition of carbon nanoclusters. The thicknesses of the nanosheets are at the scale of nanometer, as determined by the Scanning Electron Microscope measurement of curled nanosheets. The characterization by Raman scattering and the Electron Backscattered Diffraction demonstrated the graphitic structure of the nanosheets. Comparable growth was also carried out with the conditions of silicon substrates or free deposition. No similar nanosheet was found. The lattice match and the beam energy are attributed to enhance the graphitic growth. [Copyright &y& Elsevier]

Abstract: Non-invasive assay for the early stage diagnosis of methicillin resistant Staphylococcus aureus ( MRSA ) related pneumonia is of great clinical importance and still a great challenge. In this paper, we reported a novel kind of Au@Ag core–shell theranostic nanoparticles (NPs) conjugated with MRSA specific antibody on their surface. Compared with the raw Au@Ag NPs, these antibody modified NPs (AAMA NPs) showed 10.66 fold enhancement targeting to the MRSA in vitro. In vivo target efficacy was measured with rats bearing pneumonia induced by different pathogens. Computed tomography (CT) results revealed that these AAMA NPs had higher CT contrast enhancement (498 HU), than those of raw Au@Ag and Omnipaque (oth <100 HU). In addition, lesions labeled by AAMA NPs could be distinguished from lung parenchyma by taking advantage of spectra CT. Bio-distribution analysis confirmed that these AAMA NPs accumulated in the MRSA rich site. Both BAL and Elisa assays indicated that these AAMA NPs greatly alleviated the inflammation reaction by reducing bacterial proliferation and cytokine production. Pathological study showed that these NPs exerted negligible long term cytotoxicity in vivo. [Copyright &y& Elsevier]