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Abstract Natural systems, synthetic materials, and devices almost always feature interphases that control the flow of mass and energy or stabilize interfaces between incompatible materials. With technologies transitioning to non‐planar and 3D mesoscale architectures, novel deposition methods for realizing ultrathin coatings and interphases are required. Polymer networks are of particular interest for their tunable chemical and physical properties combined with their structural integrity. Here, the electrodeposition of polymer networks (EPoN) is introduced as a general approach to uniformly coat non‐planar conductive materials. Conceptually, EPoN utilizes electrochemically activated crosslinkers as polymer end groups to confine their network formation exclusively to the material surface upon charge transfer, yielding a passivating and self‐limiting growth of conformal and uniform coatings with tunable submicron thickness on conductive materials. EPoN is found to result in thin functional films of various polymer backbones and side group chemistries as demonstrated for poly(ether) and poly(acrylamide) based polymers as solid electrolyte and thermally responsive interphases, respectively.
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Electrodeposition of reactive polymer networks for conformal ultrathin coatings amenable to post-deposition functionalization
Functional thin coatings are crucial in modern and emerging technologies, providing specified surface properties and protection, thereby influencing the performance and lifetime of materials and devices. The electrodeposition of polymer networks (EPoN) has recently been reported as a facile and potentially broadly applicable method to fabricate conformal polymeric ultrathin films on conductive substrates with arbitrary shapes and surface topography under mild solution conditions. In this work, a new generation of EPoN is introduced that utilizes a chemically reactive polymer appended by a small fraction of a electrochemical crosslinker as side groups. This EPoN iteration eliminates the need for precise end-group functionalization, enables the tuning of crosslink density and film thickness independent of polymer size, and the resulting reactive ultrathin films are amenable to post-deposition modification with desired functionalities using facile click-chemistry. To demonstrate this concept, we electrodeposit polyisoprene with small side-group fractions of the oxidative crosslinker phenol (<5%) as a thiol–ene-reactive polymer-network coating. The EPoN-derived ultrathin films are tunable and uniform with a thickness in the 100s of nanometers depending on phenol fraction and electrodeposition potential, and show a conformal morphology on complex porous electrode architectures. We further demonstrate post-EPoN functionalization of the ultrathin polyisoprene coatings with thiol–ene chemistry.
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- Award ID(s):
- 2146597
- PAR ID:
- 10633988
- Publisher / Repository:
- Royal Society of Chemistry
- Date Published:
- Journal Name:
- Journal of Materials Chemistry A
- ISSN:
- 2050-7488
- 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/10.1039/D5TA03811A
