High Optically Transparent Coating for Electromagnetic Interference (EMI) Protection
Abstract
Electromagnetic interference (EMI) shielding is critical in multiple electronic arenas in both the private and defense sectors as devices and entire systems are open to radio communication mishaps and intentional nefarious invasions (i.e., remote hacking) if appropriately-designed EMI shielding materials are not in place. Importantly, certain applications require EMI shielding that both allows for high electrical conductivity (i.e., low sheet resistance) while also allowing large amounts of light to pass through the shielding material (i.e., to have materials with low optical absorption and low reflectance at the wavelengths of interest). To date, inorganic metal-oxide materials [e.g., tin-doped indium oxide (ITO)] have filled this role; however, the optical absorption properties of these materials are not ideally suited for the entire wavelength range of interest. As such, a critical need exists to develop materials solutions that allow for highly conductive, highly transparent coatings to be had, and, ideally, these materials should be designed such that they can be processed in high-throughput, low-cost manners. Here, we address this need through the development of next-generation conducting polymer solutions that will markedly change the current paradigm regarding transparent EMI shielding technologies. We anticipate providing an EMI shielding solution that provides for extremely low sheet resistance values, extremely high transparency values across a wide range of wavelengths, and that can be coated using low-cost manners across a variety of substrate dimensions and form factors. In order to accomplish this overarching objective, we will advance previous materials design research breakthroughs that occurred in the laboratories of team such that we are able to make this impact in a deep and relatively rapid manner. Specifically, we will: 1. Manipulate the doping levels and the formulation conditions associated with two promising classes of conducting polymer materials in a strategic manner to optimize the optoelectronic properties of the solution-processable macromolecular conductors in order to achieve the desired performance metrics. We will rely on two distinct classes of materials, one based on a conjugated macromolecular backbone motif and the other that is based on non-conjugated radical polymers (i.e., macromolecules with aliphatic carbon backbones and with open-shell groups at the pendant sites of the materials) to address these design parameters. This is because our previous success with these materials gives us extreme confidence that appropriate doping and processing of these materials will result in high-performance EMI shielding systems. 2. Establish the robustness and operational stability of the polymer conductors when they are exposed to a variety of environmental conditions. In this way, we will ensure that the organic electronic materials have operational lifetimes that are consistent with the current state-of-the-art inorganic electronic materials solutions to EMI shielding. 3. Demonstrate the scalability of producing uniform thin films of these materials across large substrate areas and form factors that are of interest to the Department of Defense using scalable printing technologies (e.g., roll-to-roll coating and spray coating). In this way, we envision being able to provide EMI shielding solutions that meet the aggressive metrics associated with the call while adding the extra value of having a high-throughput fabrication strategy in place for rapid deployment of the technology. In accomplishing these objectives, we envision providing a clear and long-lasting benefit to the Department of Defense as we will have created a new materials class that provides transparent EMI coatings solutions to the defense community.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- May 19, 2020
- Source ID
- N001642011002
Entities
People
- Bryan W Boudouris
Organizations
- Naval Surface Warfare Center
- United States Navy
- University of Virginia