Research

Nature achieves remarkable selectivity and efficiency by confining chemical processes at the nanoscale and arranging those confined domains into hierarchical structures that span meso- to macroscopic scales. Those organized architectures enable precise regulation, fast responses, and high overall performance. Our research aims to replicate this resource- and energy-efficient behavior in synthetic systems by closing key knowledge gaps. To do that, we study and develop methods to synthesize and place different functional elements with high spatial fidelity across the mesoscale, drawing on fundamental principles of complex fluids and gels, polymer self-assembly, nanoconfinement, and electrochemistry. Major areas of research are outlined below.

3-D Thin Films: Electrodeposition of Polymer Networks

The precise and conformal deposition of functional materials as sub-micron films and coatings is well-established in 2-D and on external surfaces, but existing fabrication methods struggle to uniformly coat 3-D architectures such as non-planar substrates and porous materials with mesoscale feature sizes. We invented the Electrodeposition of Polymer Networks (EPoN) to enable conformal and uniform functional coatings on 3D and porous conductive materials. EPoN combines polymer network chemistry and electrochemistry to achieve self-limiting film growth with nanometric tunability. We recently expanded our approach to reactive EPoN that allows for facile post-deposition functionalization of the coatings.  EPoN enables multifunctional 3-D materials with large interphase areas and tailor-made properties of interest for energy and separation technologies. (Related publications)

Architected Materials and Devices

Low-Tortuosity Architectures to Mitigate Mass Transfer Limitations
We study and develop fabrication methods to fabricate rationally architected materials at application-relevant scales with control from the nano- to the micron- and the macro-scale. Specifically, in our recent work we demonstrate how electrodes with micron-sized low-tortuosity channels can be fabricated in a tunable, scalable, and material agnostic method using hybrid phase inversion. We further showed that control over the sub-micron porosity is obtained through various secondary phase separation and gelation phenomena. We use the structural tunability of the multiscale architected and hierarchically porous materials to gain insights into mass-transfer-limited applications such as electrochemical energy storage and separation of dilute species in combination with EPoN-derived coatings.  (Related publications)

3-D Micro-Interdigitated Battery Architectures
Departing from the traditional 2-D layered battery design and integrating all battery components inside a 3-D structure has the potential to result in ultra-short ion diffusion distances between the electrodes in an architecture with macroscopic dimensions and high functional material density. This enables decoupling of a battery’s energy from its power density to a large degree, using rational structural design considerations. We research the fabrication methods and synthesis pathways of such complex 3-D battery architectures using bottom-up synthesis strategies such as combining our EPoN and HIPI concepts, and we study their fundamental properties and limitations.

Crosslinked Block Copolymer Monoliths and Gels

We study the nanoconfined swelling, molecular transport, and deposition chemistry in monolithic crosslinked block copolymer gels (xBCP). As a bottom-up fabrication method, block copolymer self-assembly enables the creation of complex architectures with characteristic feature sizes on the sub-100 nanometer scale over large volumes such as monolithic materials. We developed a modular approach that creates 1-D, 2-D, and 3-D periodically ordered materials of triblock terpolymers with one block crosslinked at tunable crosslink density & composition, and two other blocks providing tailored functionality. We demonstrated for the first time that these materials form ordered homogeneous organogels even at liquid fractions above 80%, as well as selectively swollen hydrogels with zwitterionic channels. The modular physico-chemical properties of our materials are well suited for systematic parametric studies of, for example, molecular and ion transport. Additionally, the gels can be used as ordered nanoreactors to fabricate functional mesoporous materials via selective infusion templating (SIT). (Related publications)

Autonomous Polymer Materials Discovery

Thanks to the modularity of reactive polymer networks and the automation friendliness of electrodeposition, we recognize that our reactive EPoN paradigm lends itself to high-throughput autonomous discovery of polymer films. To this end, we built, validated, and are employing the Polymer Discovery and Analysis Array (PANDA) in collaboration with the group of Prof. Keith Brown at BU. The PANDA is capable of automated fluid handling, well-plate-based electrochemistry and electrodeposition, together with optical and spectroscopic characterization of the polymer films. Enabled by EPoN and integrated with machine-learning-based analysis and decision making, we implement and perform autonomous discovery campaigns of advanced polymer materials towards functions such as omniphobicity, electrochromism, and ionic conductivity, amongst others. Anyone interested in ideation or collaborating on autonomous polymer-materials discovery campaigns is welcome to reach out to us. (Related publications)