Galvanic replacement reactions have been widely used to transform solution dispersed silver template structures into intricate nanoshell geometries. Here, we report on the use of these same reactions to form hollow su...Galvanic replacement reactions have been widely used to transform solution dispersed silver template structures into intricate nanoshell geometries. Here, we report on the use of these same reactions to form hollow substrate-supported Au-Ag nanoshells from silver templates having a heteroepitaxial relationship with the underlying single crystal substrate. The structures obtained exhibit a nanohut geometry, show highly tunable plasmonic properties and are formed as periodic arrays using a lithography-free technique. When removed from the substrate the inverted nanohuts appear as nanobowls with a notch in the rim. The study lays the groundwork for wafer-based devices utilizing nanoshells located at site-specific locations.展开更多
Hetero-assembling of spherical building blocks with well-defined spatial distribution holds great significance in developing chiral nanostructures. Herein, a strategy for hetero-assembling of gold nanoparticles(Au NPs...Hetero-assembling of spherical building blocks with well-defined spatial distribution holds great significance in developing chiral nanostructures. Herein, a strategy for hetero-assembling of gold nanoparticles(Au NPs) was demonstrated using rigid bifacial DNA origami as templates. By tuning the sizes and the fixed location of Au NPs on DNA origami, right-handed and left-handed Au NPs nanostructures were respectively constructed. Gel electrophoresis indicated the formation of the DNA origami-Au NPs complex and transmission electron microscopy(TEM) visually displayed the arrangement of Au NPs in these two chiral structures. The spatial configuration and 3D geometry of Au NPs were further illustrated by the stereographic TEM with tilting angles from ?30° to 30°. This strategy provides a universal approach to construct the asymmetrical 3D geometries, which may have potential applications in biomimicking and nanophotonics.展开更多
Dislocation dynamics simulations are performed to investigate the effect of template shape on the nanoimprinting of metal layers. To this end, metal thin films are imprinted by a rigid template made of an array of equ...Dislocation dynamics simulations are performed to investigate the effect of template shape on the nanoimprinting of metal layers. To this end, metal thin films are imprinted by a rigid template made of an array of equispaced indenters of various shapes, i.e., rectangular, wedge, and circular. The geometry of the indenters is chosen such that the contact area is approximately the same at the final imprinting depth. Results show that, for all template shapes, the final patterns strongly depend on the dislocation activity, and that each imprint differs from the neighboring ones. Large material pile ups appear between the imprints, such that polishing of the metal layer is suggested for application of the patterns in electronics. Rectangular indenters require the lowest imprinting force and achieve the deepest retained imprints.展开更多
文摘Galvanic replacement reactions have been widely used to transform solution dispersed silver template structures into intricate nanoshell geometries. Here, we report on the use of these same reactions to form hollow substrate-supported Au-Ag nanoshells from silver templates having a heteroepitaxial relationship with the underlying single crystal substrate. The structures obtained exhibit a nanohut geometry, show highly tunable plasmonic properties and are formed as periodic arrays using a lithography-free technique. When removed from the substrate the inverted nanohuts appear as nanobowls with a notch in the rim. The study lays the groundwork for wafer-based devices utilizing nanoshells located at site-specific locations.
基金supported by the National Basic Research Program of China (2012CB933301)the National Natural Science Foundation of China (21305070, 21475064)+2 种基金the Natural Science Foundation of Jiangsu Province (BK20130861)the Sci-tech Support Plan of Jiangsu Province (BE2014719)Science Foundation of Nanjing University of Posts and Telecommunications (213005, 214175).
文摘Hetero-assembling of spherical building blocks with well-defined spatial distribution holds great significance in developing chiral nanostructures. Herein, a strategy for hetero-assembling of gold nanoparticles(Au NPs) was demonstrated using rigid bifacial DNA origami as templates. By tuning the sizes and the fixed location of Au NPs on DNA origami, right-handed and left-handed Au NPs nanostructures were respectively constructed. Gel electrophoresis indicated the formation of the DNA origami-Au NPs complex and transmission electron microscopy(TEM) visually displayed the arrangement of Au NPs in these two chiral structures. The spatial configuration and 3D geometry of Au NPs were further illustrated by the stereographic TEM with tilting angles from ?30° to 30°. This strategy provides a universal approach to construct the asymmetrical 3D geometries, which may have potential applications in biomimicking and nanophotonics.
基金Project (No VENI 08120) supported by the Dutch National Scientific Foundation NWO and Dutch Technology Foundation STW
文摘Dislocation dynamics simulations are performed to investigate the effect of template shape on the nanoimprinting of metal layers. To this end, metal thin films are imprinted by a rigid template made of an array of equispaced indenters of various shapes, i.e., rectangular, wedge, and circular. The geometry of the indenters is chosen such that the contact area is approximately the same at the final imprinting depth. Results show that, for all template shapes, the final patterns strongly depend on the dislocation activity, and that each imprint differs from the neighboring ones. Large material pile ups appear between the imprints, such that polishing of the metal layer is suggested for application of the patterns in electronics. Rectangular indenters require the lowest imprinting force and achieve the deepest retained imprints.
