Search Results
Gold Aerogels: Three-Dimensional Assembly of Nanoparticles and Their Use as Electrocatalytic Interfaces
2016, Wen, Dan, Liu, Wei, Haubold, Danny, Zhu, Chengzhou, Oschatz, Martin, Holzschuh, Matthias, Wolf, André, Simon, Frank, Kaskel, Stefan, Eychmüller, Alexander
Three-dimensional (3D) porous metal nanostructures have been a long sought-after class of materials due to their collective properties and widespread applications. In this study, we report on a facile and versatile strategy for the formation of Au hydrogel networks involving the dopamine-induced 3D assembly of Au nanoparticles. Following supercritical drying, the resulting Au aerogels exhibit high surface areas and porosity. They are all composed of porous nanowire networks reflecting in their diameters those of the original particles (5–6 nm) via electron microscopy. Furthermore, electrocatalytic tests were carried out in the oxidation of some small molecules with Au aerogels tailored by different functional groups. The beta-cyclodextrin-modified Au aerogel, with a host–guest effect, represents a unique class of porous metal materials of considerable interest and promising applications for electrocatalysis.
Copolymerization of zinc-activated isoindigo- and naphthalene-diimide based monomers: an efficient route to low bandgap π-conjugated random copolymers with tunable properties
2016, Karpov, Yevhen, Maiti, Jatindranath, Tkachov, Roman, Beryozkina, Tetyana, Bakulev, Vasiliy, Liu, Wei, Komber, Hartmut, Lappan, Uwe, Al-Hussein, Mahmoud, Stamm, Manfred, Voit, Brigitte, Kiriy, Anton
The present work aims at the extension of the scope of a recently discovered polycondensation of AB-type anion-radical monomers. To this end, we investigate the polymerization of isoindigo-based monomer and its copolymerization with the naphthalenediimide-based monomer. Although polycondensations of parent naphthalenediimide- and perylenediimide-based monomers involve chain-growth mechanism, we found that the corresponding isoindigo-based monomer polymerizes in a step-growth manner under the same reaction conditions. In contrast to Stille, Suzuki and direct arylation polycondensations which require prolonged stirring at high temperatures, the polymerization approach we employed in this study proceeds fast at room temperature. It was found that near statistical copolymerization of isoindigo-based anion-radical monomers with corresponding naphtalenediimide-based monomers proceeds smoothly resulting in a library of copolymers with varying composition and properties depending on the ratio of the monomers.
Nickel cobalt oxide hollow nanosponges as advanced electrocatalysts for the oxygen evolution reaction
2015, Zhu, Chengzhou, Wen, Dan, Leubner, Susanne, Oschatz, Martin, Liu, Wei, Holzschuh, Matthias, Simon, Frank, Kaskel, Stefan, Eychmüller, Alexander
A class of novel nickel cobalt oxide hollow nanosponges were synthesized through a sodium borohydride reduction strategy. Due to their porous and hollow nanostructures, and synergetic effects between their components, the optimized nickel cobalt oxide nanosponges exhibited excellent catalytic activity towards oxygen evolution reaction.
Carbon-Based Materials at Nanoscale
2015, Xia, Dan, Otyepka, Michal, Li, Xi, Liu, Wei, Zheng, Qingbin
[No abstract available]