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Microscale continuous thin films or patterned conductive structures find applications in thin film electronics, energy generation and functional sensor systems. An emerging alternative to conventional vacuum based deposition of such structures is the additive deposition and sintering of conductive nanoparticles, to enable low temperature, low-cost and low energy fabrication. While significant work has gone into additive deposition of nanoparticles the realization of the above potential needs nanoparticle sintering methods that are equally low-cost, in-situ, ambient condition and desktop-sized in nature. This work demonstrates the integration of non-laser based, low-cost and small footprint optical energy sources for ambient condition sintering of conductive nanoparticles, with wide-area aerosol jet based additive printing of nanoparticle inks. The nanoparticle sintering is characterized by quantifying the sintering temperatures, sintered material conductivity, crystallinity, optical properties, thickness and microscale morphology in terms of the sintering parameters. It is shown that such optical sintering sources can be further integrated with inkjet printing as well, and the implications on new paradigms for hybrid additive-
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3D printed polyamide membranes for desalination
Polyamide thickness and roughness have been identified as critical properties that affect thin-film composite membrane performance for reverse osmosis. Conventional formation methodologies lack the ability to control these properties independently with high resolution or precision. An additive approach is presented that uses electrospraying to deposit monomers directly onto a substrate, where they react to form polyamide. The small droplet size coupled with low monomer concentrations result in polyamide films that are smoother and thinner than conventional polyamides, while the additive nature of the approach allows for control of thickness and roughness. Polyamide films are formed with a thickness that is controllable down to 4-nanometer increments and a roughness as low as 2 nanometers while still exhibiting good permselectivity relative to a commercial benchmarking membrane.
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- Award ID(s):
- 1726862
- PAR ID:
- 10193996
- Date Published:
- Journal Name:
- Science
- Volume:
- 361
- Issue:
- 6403
- ISSN:
- 0036-8075
- Page Range / eLocation ID:
- 682 to 686
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1126/science.aar2122
