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Doughnut-shaped ZnO microparticles have been grown through a hydrothermal reaction in citrate solution at 120 degrees C. FESEM reveals that these microparticles consist of regular arranged nanoplates, and there is a concave on the surface of each microparticle. The existence of citrate is vital to the formation of the complex microparticles. Room temperature photoluminescence measurements show strong UV band emission. The yellow and green emissions related to the structure defects can be barely observed, indicating the high crystalline perfection of these microparticles. 相似文献
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We present a novel approach for preparation of nanometric protein arrays, based on binding of avidin molecules to nanotemplates generated by conductive AFM lithography on robust oligo(ethylene glycol)-terminated monolayers on silicon (111) surfaces that are protein-resistant. We showed that only biotinated-BSA but not the native BSA bind to the avidin arrays and that the resulting arrays of biotinated BSA could bind avidin to form protein dots with a feature size of approximately 30 nm. This result demonstrates that the avidin array may serve as templates for preparation of nanoarrays of a wide variety of biotin-tagged proteins for studying their interactions with other protein molecules at nanoscale. 相似文献
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Recent experiments suggest that the high hydrogen storage capacity in graphite nanostructures might be associated with adsorption on the edges. First-principles calculations are used to study the structure and energetics of H chemisorption on graphite zigzag edges. The properties of both singly and doubly hydrogenated edges are examined. Molecular hydrogen can dissociatively adsorb on the edge directly, with small activation barriers to the formation of either singly or doubly hydrogenated structures. A new model for the location of adsorbed H is proposed. 相似文献
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Jingquan Sha Jun Peng Shujing Zhou Min Zhu Ling Han Dan Chen 《Journal of Cluster Science》2008,19(3):499-509
Two new bivanadyl capped Keggin polyoxometalate-based inorganic–organic hybrid compounds, [M(2,2′-bipy)2(H2O)]2[AsMo12O40(VO)2]}(M = Co 1, Zn 2; bipy = bipyridine), have been synthesized under hydrothermal conditions by directly using Li3[AsMo12O40] · nH2O as starting materials. Single crystal X-ray analysis revealed that compounds 1 and 2 were isostructural, consisting of a neutral bivanadyl capped Keggin POMs bigrafted by [M(2,2′-bipy)2(H2O)]2+ fragments. Other characterizations by elemental analysis, IR spectra, XPS spectra, power X-ray diffraction and TG analysis
were also described in the paper. The study of the electrochemical properties of compounds 1 and 2 exhibit similar redox behaviors, undergoing three two-electron reversible redox processes, and the electrocatalysis of 1 has also been studied in detail.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
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