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Article“Green” Fabrication of High-performance Transparent Conducting Electrodes by Blade Coating and Photonic Curing on PET for Perovskite Solar CellsJustin C. Bonner 1,†, Robert T. Piper 1,†, Bishal Bhandari 2, Cody R. Allen 2, Cynthia T. Bowers 3,4, Melinda A. Ostendorf 3,4, Matthew Davis 5, Marisol Valdez 6, Mark Lee 2 and Julia W. P. Hsu 1,∗1 Department of Materials Science and Engineering, University of Texas at Dallas, 800 W Campbell Road, RL-10, Richardson, TX 75080, USA2 Department of Physics, University of Texas at Dallas, 800 W Campbell Road, Richardson, TX 75080, USA3 Materials Characterization Facility at the Air Force Research Laboratory, 2941 Hobson Way, WPAFB, OH 45433, USA4 UES, Inc., a BlueHalo Company, 4401 Dayton-Xenia Rd, Dayton, OH 45432, USA5 Energy Materials Corporation, 1999 Lake Ave B82 Ste B304, Rochester, NY 14650, USA6 Department of Chemistry, University of Texas at Dallas, 800 W Campbell Road, Richardson, TX 75080, USA* Correspondence: jwhsu@utdallas.edu† These authors contributed equally to this work.Received: 30 September 2024; Revised: 25 October 2024; Accepted: 30 October 2024; Published: 5 November 2024Abstract: This study presents an innovative material processing approach to fabricate transparent conducting electrodes (TCEs) on polyethylene terephthalate (PET) substrates using blade coating and photonic curing. The hybrid TCEs consist of a multiscale Ag network, combining silver metal bus lines and nanowires, overcoated by an indium zinc oxide layer, and then photonically cured. Blade coating ensures film uniformity and thickness control over large areas. Photonic curing, a non-thermal processing method with significantly lower carbon emissions, enhances the conductivity and transparency of the coated layers. Our hybrid TCEs achieve an average transmittance of (81 ± 0.4)% referenced to air ((90 ± 0.4)% referenced to the PET substrate) in the visible range, an average sheet resistance of (11 ± 0.5) Ω sq−1, and an average surface roughness of (4.3 ± 0.4) nm. We benchmark these values against commercial PET/TCE substrates. Mechanical durability tests demonstrate <3% change in resistance after 2000 bending cycles at a 1 in radius. The scalable potential of the hybrid TCE fabrication method is demonstrated by high uniformity and excellent properties in 7 in × 8 in large-area samples and by performing the photonic curing process at 11 m min−1. Furthermore, halide perovskite solar cells fabricated on these hybrid TCEs achieve average and champion power conversion efficiencies of (10.5 ± 1.0) % and 12.2%, respectively, and significantly outperform devices made on commercial PET/TCEs. This work showcases our approach as a viable pathway for high-speed “green” manufacturing of high-performance TCEs on PET substrates for flexible optoelectronic devices.
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This content will become publicly available on March 31, 2026
Fabricating Silver Nanowire–IZO Composite Transparent Conducting Electrodes at Roll-to-Roll Speed for Perovskite Solar Cells
This study addresses the challenges of efficient, large-scale production of flexible transparent conducting electrodes (TCEs). We fabricate TCEs on polyethylene terephthalate (PET) substrates using a high-speed roll-to-roll (R2R) compatible method that combines gravure printing and photonic curing. The hybrid TCEs consist of Ag metal bus lines (Ag MBLs) coated with silver nanowires (AgNWs) and indium zinc oxide (IZO) layers. All materials are solutions deposited at speeds exceeding 10 m/min using gravure printing. We conduct a systematic study to optimize coating parameters and tune solvent composition to achieve a uniform AgNW network. The entire stack undergoes photonic curing, a low-energy annealing method that can be completed at high speeds and will not damage the plastic substrates. The resulting hybrid TCEs exhibit a transmittance of 92% averaged from 400 nm to 1100 nm and a sheet resistance of 11 Ω/sq. Mechanical durability is tested by bending the hybrid TCEs to a strain of 1% for 2000 cycles. The results show a minimal increase (<5%) in resistance. The high-throughput potential is established by showing that each hybrid TCE fabrication step can be completed at 30 m/min. We further fabricate methylammonium lead iodide solar cells to demonstrate the practical use of these TCEs, achieving an average power conversion efficiency (PCE) of 13%. The high-performance hybrid TCEs produced using R2R-compatible processes show potential as a viable choice for replacing vacuum-deposited indium tin oxide films on PET.
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- Award ID(s):
- 2135203
- PAR ID:
- 10580466
- Publisher / Repository:
- MDPI
- Date Published:
- Journal Name:
- Nanomanufacturing
- Volume:
- 5
- Issue:
- 2
- ISSN:
- 2673-687X
- Page Range / eLocation ID:
- 5
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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