Assembly of Gold Nanowires on Gold Nanostripe Arrays: Simulation and Experiment

Abstract

Nanowires (NWs) have a large aspect ratio and large available surface area, which have made them a potential platform for applications in biosensors as well as electronic/optic and power storage devices. However, the realization of many of these applications requires the wires to be positioned and oriented through an assembly process. Hence, it is essential to develop assembly strategies and techniques to achieve a variety of desired structures. In this work, we explored NW assembly using a patterned NW–substrate interaction. Experimentally, silica-coated Au nanowires (diameter of 340 nm, lengths of 2.4 and 4.4 μm, 30 nm SiO2 shell) are allowed to self-assemble onto microfabricated Au features that create a series of “stripes” on a glass substrate (feature height of 50–200 nm; widths of 2.4, 4.5, and 4.8 μm). We observe a rich variety of patterns, with NWs concentrated atop the Au features and oriented perpendicular and diagonal to the stripe axes. We develop a model of this system by considering the relevant van der Waals and electrostatic interactions among NWs and between the NWs and stripes. Monte Carlo simulations of the assembly were performed based on this model, and good agreement with the experiment was achieved. An interesting finding from this work is that extra repulsion at the NW ends plays an important role in determining whether NWs order with their long axes parallel or perpendicular to the Au stripe axis. The simplicity of our approach makes this platform a promising way to achieve more elaborate nanoparticle assemblies in the future.

Local Field Induced Mass Transfer: New Insight into Nano‐electrocatalysis

“…This mechanism is also intended to be utilized in other configurations or electrocatalytic systems, such as enhancing ionic conductivity in composite polymer electrolytes with wellaligned ceramic nanowires, [58] facilitating charge storage at electrified interfaces with self-assembled nanostructures in ionic liquids, [59] fabricating structurally ordered ionic liquid-layered double hydroxide to amplify chemiluminescence signals, [60] structuring hollow Palladium-Gold nanochains with periodic concave structures as superior oxygen reduction reaction electrocatalysts and highly efficient surface-enhanced Raman scattering substrates, [61] assembling of gold nanowires on gold nanostripe arrays for applications in electronic/optic and power storage devices [62] as well as mechanical design of brush coating technology for the alignment of one-dimension nanomaterials. [63] Apart from assembling 1D nano materials in ordered configuration, aligning them into 3D channel also proved to be an efficient way inspiring high electrocatalytic performance.…”

Development of the ReaxFF Reactive Force Field for Cu/Si Systems with Application to Copper Cluster Formation during Cu Diffusion Inside Silicon

“…The control of impurity contamination in the manufacturing of semiconductor devices has been identified as a critical issue due to their severe impact on the performance of microelectronics . Metallic impurities can be introduced during crystal formation or the fabrication process. − It has been reported that the 3d transition-metal impurities like Mn, Fe, Co, Ni, and Cu in silica and silicon compounds induce a variety of chemical activities contributing to the alterations in device performance . Nowadays, due to copper’s lower bulk resistivity and high activation energy compared to aluminum, copper is considered a suitable alternative for Al in the design of ultra-large-scale integration (ULSI) devices .…”

Connectedness percolation in the random sequential adsorption packings of elongated particles

“…In recent years, the different patterns of self-assembly occuring in random packings of elongated particles onto two-dimensional (2D) substrates have attracted a great deal of attention [1]. Such assemblies may have attractive practical applications in memory devices, the preparation of substrates with controlled wettability, transparent electrodes for optoelectronics, and for sensing materials [2,3].…”