Break

Porous materials are essential components for many applications because they must facilitate mass transfer, provide active surfaces for chemical reactions, and conduct electrons and heat. Additionally, they must maintain long-term stability under operating conditions, resistance under mechanical stresses, and low-weight. Novel energy storage and conversion devices use porous materials, which drastically affect the performance. In fuel cells, porous carbon substrates are responsible for accurately controlling the complex two-phase mass transfer phenomenon through diffusion layers and facilitating triple-phase-boundaries in the catalyst layers. In redox flow batteries, porous electrodes are responsible for liquid electrolyte distribution and provide active surfaces for electrochemical reactions. Solid-state diffusion of lithium is a major performance limitation in lithium-ion batteries. The lack of sophisticated control over the microstructure and surface properties limits the performance of state-of-art materials. Additionally, the interfacial processes, such as wetting, have been largely overlooked.

The rational design of porous materials requires an understanding of structure-function relationships at multiple scales. During my future faculty position, I intend to fabricate advanced porous materials for a variety of applications relevant to chemical engineering and electrochemistry. I anticipate using simulations, such as Lattice Boltzmann and pore network modeling, to inform the experimental design of these novel materials. In this presentation, I will first briefly overview my past and current research. Then, I will discuss the future research directions that I plan to pursue, mainly: (1) synthesis of engineered porous materials with different degrees of hierarchization; (2) modification of surfaces using thin films to impart functional properties, such as wetting, electrochemical activity, or stability; (3) development of advanced characterization platforms and techniques to visualize and investigate porous materials and devices.

Research experience

PhD Thesis Project: Novel gas diffusion layers with patterned wettability for advanced water management strategies in polymer electrolyte fuel cells. Advisor: Prof. Thomas J. Schmidt (Department of Chemistry and Applied Biosciences, ETH Zurich)

(e-collection.library.ethz.ch/eserv/eth:50310/eth-50310-02.pdf).

My PhD research at ETH Zurich/Paul Scherrer Institute focused on the development of novel porous materials for fuel cell applications. During this time, I developed substantial expertise in materials science of porous media, microfluidics, imaging methods and electrochemical engineering. I invented a method, based on radiation grafting, to synthesize gas diffusion layers with patterned wettability. Monte Carlo simulations were used to theoretically predict the electron dose distribution throughout the porous materials, leading to notable improvements in resolution. The choice of monomer and reaction conditions allowed for the precise regulation of the hydrophilicity. Correlations between material microstructure, surface chemical composition, and wetting properties were elucidated, which provided a fundamental understanding about wetting in complex systems and capillary pressure transport. Additionally, we used a combination of advanced imaging techniques (e.g. neutron radiography and x-ray tomographic microscopy) and electrochemical diagnostics to understand the limiting performance factors and to inform the design of optimized materials. The modified diffusion layers with patterned wettability have improved the water management inside operando cells, thereby significantly increasing the fuel cell power density. The technology was patented and has attracted significant attention from industry. Presently, this technology is heading towards commercialization.

Postdoc Project: Development of advanced porous electrodes for non-aqueous redox flow batteries. Advisor: Prof. Fikile Brushett (Department of Chemical Engineering, MIT)

My ongoing postdoctoral work at the Massachusetts Institute of Technology focuses on the development of advanced porous electrodes for redox flow batteries. During this time, I investigated the effect of the electrode microstructure on flow battery performance. To deconvolute the role of electrode properties performance, specifically its impact on kinetics, ohmics and mass transport, we used platform redox couples, with well-defined electrochemical properties, in tandem with diagnostic flow cell configurations which enable individual electrode characterization in isolation, but at near, practical operating conditions. A key finding was that hierarchically organized microstructures, featuring a bimodal pore size distribution, greatly improve flow battery performance, informing the design of novel microstructures. To accurately understand transport within these highly anisotropic carbon-fiber electrodes, we are using X-ray tomographic microscopy to obtain detailed microstructural information and running computational fluid dynamics simulations. Furthermore, I am synthesizing metallic porous electrodes with a well-defined microstructure and composition using the dealloying method. Additionally, a variety of polymer thin films have been electrografted onto the surfaces of porous electrodes to impart desired properties, such as specific wettability, increased surface area or electrochemical activity. During this period, I am developing substantial expertise in electrode fabrication, energy storage, surface modifications through electrochemical methods, organic synthesis and numerical simulations.

Awards and Honors

• ETH Medal for Outstanding PhD Thesis, ETH Zurich, 2017
• Energy Technology Graduate Student Award, The Electrochemical Society, 2017
• Early Postdoc Mobility, Swiss National Science Foundation, 2016
• Chemical Engineering Valedictorian, University of Alicante, 2013

Selected Publications

1. Forner-Cuenca & F. Brushett, "Carbonaceous porous electrodes for non-aqueous redox flow batteries: understanding the role of microstructure", in preparation.
2. Forner-Cuenca, et al. (2017), "Mask-assisted electron radiation grafting for localized through-volume modification of porous substrates", Radiation Physics and Chemistry, 135, 133-141.
3. Forner-Cuenca, et al. (2016). "Advanced water management in PEFCs: diffusion layers with patterned wettability. Part III: In-situ PEFC characterization with neutron imaging", Journal of The Electrochemical Society, 163(13), F1389-F1398.
4. Forner-Cuenca, et al. (2016), "Advanced water management in PEFCs: diffusion layers with patterned wettability. Part II: Measurement of capillary pressure characteristic with neutron and synchrotron imaging", Journal of The Electrochemical Society, 163(9), F1038-F1048.
5. Conder, A. Forner-Cuenca, et al. (2016), "Performance-enhancing asymmetric separator for lithium-sulfur batteries", ACS Applied Materials & Interfaces, 8(29), 18822-18831.
6. Forner-Cuenca, et al (2015), "Engineered water highways in fuel cells: radiation grafting of gas diffusion layers", Advanced Materials, 27, 6317-6322.

Teaching Interests:

Transport phenomena, Surface Science, Fluid Mechanics, Energy Conversion and Storage, Porous Media, Electrochemistry