Structural color printings have broad applications due to their advantages of long-term sustainability, eco-friendly manufacturing, and ultra-high resolution. However, most of them require costly and time-consuming fabrication processes from nanolithography to vacuum deposition and etching. Here, we demonstrate a new color printing technology based on polymer-assisted photochemical metal deposition (PPD), a room temperature, ambient, and additive manufacturing process without requiring heating, vacuum deposition or etching. The PPD-printed silver films comprise densely aggregated silver nanoparticles filled with a small amount (estimated <20% volume) of polymers, producing a smooth surface (roughness 2.5 nm) even better than vacuum-deposited silver films (roughness 2.8 nm) at ~4 nm thickness. Further, the printed composite films have a much larger effective refractive index
Metal patterning via additive manufacturing has been phasing‐in to broad applications in many medical, electronics, aerospace, and automotive industries. While previous efforts have produced various promising metal‐patterning strategies, their complexity and high cost have limited their practical application in rapid production and prototyping. Herein, a one‐step gold printing technique based on anion‐assisted photochemical deposition (APD), which can directly print highly conductive gold patterns (1.08 × 107S m−1) under ambient conditions without post‐annealing treatment, is introduced. Uniquely, the APD uses specific ion effects with projection lithography to pattern Au nanoparticles and simultaneously sinter them into tunable porous gold structures. The significant influence of kosmotropic or chaotropic anions in the precursor ink on tuning the morphologies and conductivities of the printed patterns by employing a series of different ions, including Cl−ions, in the printing process is presented. Additionally, the resistance stabilities and the electrochemical properties of the APD‐printed gold patterns are carefully investigated. The high conductivity and excellent conformability of the printed Au electrodes are demonstrated with reliable performance in electrophysiological signal delivery and acquisition for biomedical applications. This work exploits the potential of photochemical‐deposition‐based metal patterning in flexible electronic manufacturing.
more » « less- NSF-PAR ID:
- 10369292
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Materials
- Volume:
- 34
- Issue:
- 32
- ISSN:
- 0935-9648
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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