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The assembly of functional nanoparticles within materials with unique architectures can improve the interfacial surfaces, defects, and active sites, which are key factors for the designing novel nanocatalysts. Nano metal–organic framework (NMOF) can be employed to fabricate nanodots-confined nanohybrids for use in electrocatalytic processes. Herein, we report a controlled synthesis of gold nanodot assembly within cobalt chalcogenide nanoshell (dots-in-shell Au/CoxSy nanohybrids). A cobalt-based NMOF (the cobalt-based zeolite imidazole framework, ZIF-67) is used as a versatile sacrificial template to yield dots-in-shell Au/CoxSy nanohybrids. Due to the synergistic effect of the well-dispersed Au nanodots and the thin CoxSy nanoshell, the obtained dots-in-shell Au/CoxSy nanohybrids exhibit enhanced performance for the oxygen evolution reaction (OER) with low overpotential values at a current density of 10 mA cm−2 and a small Tafel slope (343 mV and 62 mV dec−1, respectively).

Numerous attempts have been made to prepare electrocatalytic nanomaterials and construct electrode systems for effective water-splitting reactions. The growth of transition metal-based heterostruct...

Integration of two metal constituents into core–shell structures is an efficient strategy to prepare advanced materials for a variety of applications. The controllable synthesis of targeted bimetallic core–shell nanostructures is an important yet challenging task. Herein, bimetallic nanoparticles comprising a gold multipod nanoparticle (GMN) core and distinctive Pd shell (GMN@Pd NPs) are successfully synthesized in a facile and controllable manner. Epitaxial or islanded growth of Pd on the GMNs can be readily achieved using appropriate stabilizing agents. The controllable growth mode of the Pd layers, coupled with the unique topologies of GMNs, are advantageous for enhancing the density of active interfacial surfaces in the composites. Particularly, I-GMN@Pd NPs show substantially enhanced ORR activity compared with monometallic counterparts and excellent durability and better tolerance to the crossover effect than that of Pt/C, rendering the materials highly desirable for practical use.

Oxygen evolution reaction (OER) is considered a major challenge in the production of efficient electrochemical water splitting devices. To overcome the challenge, the development of inexpensive electrochemical catalysts with high energy conversion efficiencies is vital. Nanohybrids composed of noble metal nanoparticles and transition metal hydroxides often possess catalytically active sites that are beneficial for OER performance. In this study, we report a successful synthesis of Ni(OH)2 nanoflowers with a high degree of crystallinity and uniformity. The as-prepared Ni(OH)2 nanoflowers are employed as templates for effective and controllable loading of Au nanodots to obtain Ni(OH)2@Au nanohybrids. An examination of the OER activity reveals that Ni(OH)2@Au nanohybrids exhibit a considerably lower overpotential (η) value (390 mV) at a current density of 5 mA cm–2 and a smaller Tafel slope (120 mV dec–1) than those of Ni(OH)2 nanoflowers (540 mV and 324 mV dec–1, respectively). The OER enhancement effect is mainly attributed to the decoration of Au nanodots, inducing charge transfer from Ni to Au and thereby stabilizing the Ni species at high oxidation levels. Moreover, the uniform loading of Au nanodots on the anisotropic Ni(OH)2 nanoflowers provides more active interfacial surfaces, which are expedient to OER.

>? @A BCDEFD'.?@ G HIA"#4J@K.LM N?OPQRIA@K.2STU? VWX'LJ4YZ[ "#$%&' ? Y\VW ]. M N'CDEMN ]^Z_?`a "#@K.L Y A&Ib@ )cI]. dTVe fg hieTV jklm, .n/TVkeo ?pqrMN Cs/tuvwv x'., lTH.n/TV yzT{'se|}~"#ecu€ ‚'HI]. 'LcYƒYZ[Y\"#$%&' L()Y„ †, "#$%&' A"#9‡*2ˆ, "#‰Š‹, 8Œ8|€Ž ]. "#$%&' e+"€[Y\$%&' ‘@’, "#@’, lTH“ ”k uGA+",-./012.3€ 4Y„]. AbstractIn this paper we introduce augmented broadcasting service scenarios which combines augmented reality service with broadcasting environment. As the broadcasting environment is different from mobile service environment, there are many restrictions in developing full AR services in TV. However TV has strong benefit of large screen, high quality contents, advanced user interface for motion and voice, and smart TV applications, which means that they will enhance the possibility of success for augmented broadcasting service. This paper proposes metadata structure containing information for augmentation region, time, augmented contents, and registration information for natural composition. We also implemented test bed system comprised of authoring server, broadcasting server, and user terminal for verifying metadata in broadcasting system.Keyword : Augmented Broadcasting, Metadata, Augmented Reality