Nanoscale Heat transfer; Plasmonics; Printing; Nanoparticles; Thermofuidics; Nanostructuring
Richner P., Kress S. J. P., Norris D. J., Poulikakos D. (2016), Charge effects and nanoparticle pattern formation in electrohydrodynamic NanoDrip printing of colloids, in Nanoscale
, 8(11), 6028-6034.
Schneider J., Rohner P., Thureja D., Schmid M., Galliker P., Poulikakos D. (2016), Electrohydrodynamic NanoDrip Printing of High Aspect Ratio Metal Grid Transparent Electrodes, in Advanced Functional Materials
, 26(6), 833-840.
Richner P., Galliker P., Lendenmann T., Kress S. J. P., Kim D. K., Norris D. J., Poulikakos D. (2016), Full-Spectrum Flexible Color Printing at the Diffraction Limit, in Acs Photonics
, 3(5), 754-757.
Richner P., Eghlidi H., Kress S. J. P., Schmid M., Norris D. J., Poulikakos D. (2016), Printable Nanoscopic Metamaterial Absorbers and Images with Diffraction-Limited Resolution, in Acs Applied Materials & Interfaces
, 8(18), 11690-11697.
Schneider J., Rohner P., Galliker P., Raja S. N., Pan Y., Tiwari M. K., Poulikakos D. (2015), Site-specific deposition of single gold nanoparticles by individual growth in electrohydrodynamically-printed attoliter droplet reactors, in Nanoscale
, 7(21), 9510-9519.
Kress S. J. P., Antolinez F. V., Richner P., Jayanti S. V., Kim D. K., Prins F., Riedinger A., Fischer M. P. C., Meyer S., McPeak K. M., Poulikakos D., Norris D. J. (2015), Wedge Waveguides and Resonators for Quantum Plasmonics, in Nano Letters
, 15(9), 6267-6275.
Kress S. J. P., Richner P., Jayanti S. V., Galliker P., Kim D. K., Poulikakos D., Norris D. J. (2014), Near-Field Light Design with Colloidal Quantum Dots for Photonics and Plasmonics, in Nano Letters
, 14(10), 5827-5833.
One of the most significant roadblocks toward realizing the true potential of nanotechnology is the facile and, at the same time, precise and controlled fabrication of nanostructures. The state-of-the-art fabrication methods to date are based on both top-down (e.g. photo-and electron-beam lithography, nanoimprint lithography, focused-ion milling etc.) or bottom-up (e.g. self-assembly of nanostructures or molecular structures) approaches, or their combination. Each of these approaches has shortcomings that are difficult to overcome. For example, the top-down approach involves material waste, large equipment investment and tight environmental control, and the bottom-up approach often suffers from reliability issues. Specifically, manufacturing of 3D nanostructures with precision and reproducibility remains a formidable challenge. At the same time, emerging applications such as the use of plasmonic nanostructures for light manipulation (e.g. developing metamaterials, imaging single molecules, developing ultrasensitive chemical sensors), and for harvesting light energy efficiently (e.g. in thin photovoltaics films, fuel reforming and catalysis using localized chemistry), will greatly benefit from new approaches leading to facile fabrication of optically relevant nanostructures. Such plasmonic nanostructures function by large local-field enhancement and nanometer-scale light confinement in plasmonic single entities (nanoantennas), and are receiving a great deal of attention in the current literature. In this proposal, we aim at understanding the physical phenomena and exploiting a novel, facile approach that overcomes current hurdles in fabricating planar (2D) and in particular out-of-plane (3D) nanostructures, that could function as efficient nanoantennas. We propose to further understand, improve and exploit a recently introduced method by our group, which involves directly printing nanostructures starting from nanoparticle suspensions or solutions of precursors of the materials to be transformed into nanostructures. Our on-demand approach (termed as NanoDrip printing) is based on a specific mode of electrohydrodynamic ejection of the suspensions or solutions. The technique has already shown promising feasibility with respect to the facile printing of true 2D and 3D nanostructures. The current proposal is aimed at addressing the fundamental aspects of the process in order to advance the minimal feature size and maximum controllability achievable through NanoDrip printing, and at establishing the usefulness of the printed nanostructures in meaningful plasmonic applications. The proposed research consists of two interconnected parts:1.In the first part, we plan an in depth fundamental investigation of important aspects of the NanoDrip printing process, necessary in order to form 2D and 3D nanostructures with high precision. Systematic control of the effects of the ink vapor pressure, annealing temperature of the printed structure and the printing variables (e.g. printing voltage and pulse length) will be investigated, to better understand and quantify the influence of these parameters on the size and shape of the printed nanostructures. Target will be to form both metallic and hybrid nanopillar structures (consisting to metal and Quantum dots (QDs) assemblies), which could be used as nanoantennas. The feasibility of printing single nanoparticles on-demand, for novel applications such as site specific chemistry and catalysis, will also be explored. 2.In the second part, we will focus on selected plasmonic applications, proving the capabilities of the printed nanostructures, using optical characterization and modeling. The emphasis will be kept on devising nanoantennas that are very difficult to fabricate using conventional techniques, e.g. single and arrays of printed 3D nanopillar structures with various out of plane orientations. Metallic and dielectric nanoparticles (including QDs) in suspensions will be used to print both pristine and hybrid nanoantennas. Optical spectroscopy will be used for nanoantenna characterization and for exploring the use of such nanostructures in thin-film white light absorbers.The overall goal of this study is to further develop and complete the fundamental science base for the NanoDrip printing process, in order to advance the capabilities of this novel method, including the complex optical characterization of directly printed optical nanoantennas, generated with this process in a facile manner. In addition to their fundamental value, the results of the study will also help advance an entirely novel approach of low-cost nanostructuring for technological applications.