Inkjet printing is rapidly emerging as a means to fabricate low‐cost electronic devices; however, its widespread adoption is hindered by the complexity of the inks and the relatively high processing temperatures, limiting it to only a few metals and substrates. A new approach for inkjet printing is described, based on commercially available, particle‐free inks formulated from inorganic metal salts and their subsequent low‐temperature conversion to metallic structures by a non‐equilibrium, inert gas plasma. This single, general method is demonstrated for a library of metals including gold (Au), silver (Ag), copper (Cu), palladium (Pd), platinum (Pt), lead (Pb), bismuth (Bi), and tin (Sn). As one figure of merit, the resistivities of the printed metals are measured to be between 2× and 10× of the respective bulk metals. Uniquely, it is found that the printed metal films exhibit a very large surface area because of the plasma‐initiated nucleation and growth process, making this technique attractive for sensing device applications. A Bi‐based trace Pb sensor, an Au‐based amyloid‐β42sensor, and an Au‐based strain gauge are fabricated as representative chemical, biological, and mechanical sensors, and are found to exhibit enhanced sensitivity compared to analogues made with conventional methods.
The nanomaterial landscape is so vast that a high-throughput combinatorial approach is required to understand structure–function relationships. To address this challenge, an approach for the synthesis and screening of megalibraries of unique nanoscale features (>10,000,000) with tailorable location, size, and composition has been developed. Polymer pen lithography, a parallel lithographic technique, is combined with an ink spray-coating method to create pen arrays, where each pen has a different but deliberately chosen quantity and composition of ink. With this technique, gradients of Au-Cu bimetallic nanoparticles have been synthesized and then screened for activity by in situ Raman spectroscopy with respect to single-walled carbon nanotube (SWNT) growth. Au3Cu, a composition not previously known to catalyze SWNT growth, has been identified as the most active composition.
more » « less- NSF-PAR ID:
- 10081683
- Publisher / Repository:
- Proceedings of the National Academy of Sciences
- Date Published:
- Journal Name:
- Proceedings of the National Academy of Sciences
- Volume:
- 116
- Issue:
- 1
- ISSN:
- 0027-8424
- Page Range / eLocation ID:
- p. 40-45
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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