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ABSTRACT Silver (Ag) is widely used for antimicrobial textiles due to its strong biocidal activity, but conventional Ag coating methods are often expensive and involve complex processing steps. In this study, we present a simple, solution‐based approach using polydopamine (PDA)‐assisted electroless Ag plating, which enables uniform Ag deposition on textiles with improved scalability. We systematically investigate the effects of pH, temperature, and oxygen concentration on the growth kinetics of Ag nanoparticles (NPs) during PDA‐assisted electroless Ag plating. Results show that elevated temperature (65°C), alkaline solution (pH = 10), and increased oxygen purging (50 sccm) each significantly accelerates Ag NP deposition, with coverage up to 56.69% and particle sizes up to 69.48 ± 14.89 nm. Optical and structural analyses confirmed enhanced PDA deposition as the key to expediting Ag NP growth on various textiles. Using this accelerated process, we developed a cost‐effective, 3D‐printed roll‐to‐roll system to scale up fabrication, achieving rapid and uniform Ag NP deposition. The resulting textiles exhibited superior antimicrobial properties, offering an affordable and effective solution for high‐performance hygiene applications.
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This content will become publicly available on January 30, 2026
Polydopamine‐Assisted Electroless Deposition of Magnetic Functional Coatings for 3D‐Printed Microrobots
Magnetic microrobots are attractive tools for operation in confined spaces due to their small size and untethered wireless operation, particularly in biomedical and environmental applications. Over years of development, many microrobot fabrication methods have been developed; however, they typically require costly specialized physical vapor deposition (PVD) vacuum instrumentation and present homogeneity and conformality coating problems (especially in complex 3D structures). Herein, a solution‐based polydopamine (PDA)‐assisted electroless deposition method is developed to deposit a superparamagnetic nickel thin film on microrobots. The multilayered functional film design comprises PDA as an adhesive primer and reducing agent, silver nanoclusters as catalysts, and a nickel magnetic top film, all deposited in a batch solution‐based process on glass and 3D‐printed polymer substrates. This multilayer magnetic coating is implemented and demonstrated in three magnetic microrobot archetypes, including arbitrarily‐shaped active particles, microrollers, and helical swimming microrobots, each using distinct actuation working mechanisms. Due to the material‐independent interfacial adhesive properties of PDA, this multilayer functionalization strategy can open up new magnetic microrobot fabrication schemes with a broad compatibility with materials and structures (including complex 3D‐printed polymer microstructures) and without the need for and limitations of PVD coating approaches.
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- Award ID(s):
- 2309029
- PAR ID:
- 10596650
- Publisher / Repository:
- Wiley-VCH GmbH
- Date Published:
- Journal Name:
- Advanced Intelligent Systems
- ISSN:
- 2640-4567
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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