ELECTRODEPOSITION OF POLYMER NETWORKS (EPON) AS CONFORMAL ULTRATHIN COATINGS

Functional coatings and interphases are omnipresent in modern technology and often determine the performance and lifetime of devices. For example, in solid-state energy storage devices, electrolyte-type polymeric interfaces between battery components such as the active electrode material and solid electrolyte could overcome some of these incompatibility detriments and the increase in contact resistance over long-term operation. However, existing coating strategies are incompatible with emerging mesoscaled 3D architected and porous materials and fail to uniformly apply functional thin films on their large and complex interior 3D surface. In this thesis, electrodeposition of polymer network (EPoN) is introduced to address the challenge for obtaining conformal polymeric thin films. The dual-functional molecular design possesses both self-limiting electrodeposition capability and the functionality of interest in separate molecular motifs. To exemplify this approach, lithium-ion conducting oligo/poly(ethylene oxide) is chosen as the core motif and modified with electrochemically active phenol endgroups. The comprehensive study of the processing-structure-property relationships reveals the tailorable control over the thickness, molecular permeability, and electronic properties. The demonstrated capability of conformably coating functional polymer thin films on a 3D porous electrode shows great potential in fabricating polymeric electrolyte or separators for high-performance 3D batteries. As an extension, a new generation of EPoN, reactive EPoN, is introduced that utilizes a chemically reactive polymer appended by a small fraction of eX-linker side groups. This EPoN iteration eliminates the need for precise end-group functionalization, and the resulting reactive ultrathin films are amenable to further post-deposition modification with desired functionalities. The modularity of the dual-functional molecular design enables a large library of core molecules which are not only restricted in homopolymers but also blaze a new trail for block-co-polymer and colloidal deposition on arbitrary 3D structures.

Author dc:creator

• Wang, Wenlu

Advisor dc:contributor.advisor

• Werner, Jörg G.

• Materials Science
• 3D structured materials
• thin film deposition

Language dc:language.iso

en_US

Handle dc:identifier.uri

https://hdl.handle.net/2144/51131

OAI identifier oai:identifier

oai:open.bu.edu:2144/51131