Elucidating Energy Storage in Soft Nanostructures through Versatile Electrochemistry
Dr. Joaquín Rodríguez-López
Assistant Professor
Department of Chemistry, University of Illinois at Urbana-Champaign

My group is interested in exploring the impact of structural and reactive heterogeneity in soft materials for
energy storage. New materials and an expanded electroanalytical toolbox is allowing us to discover
synergies at the nano and mesoscale for emerging battery technologies. In my talk, I will discuss two
systems where nano-scale heterogeneity has an impact on macro-scale performance: novel redox active
polymers (RAPs) for size-selective flow batteries, and ultra-thin graphene electrodes. Highly soluble RAPs
are new players in redox flow technologies, and as part of our collaboration with the Joint Center for
Research Energy Storage (JCESR), we are exploring the opportunities that polymeric design offers for
tuning their electrochemical performance. Likewise, graphene is an emerging material that offers new
opportunities in contrast to bulk carbon due to its unique thickness-dependent electron and ion transfer
behavior. In both cases, short range interactions between their components determine charge transfer and
transport mechanisms. It is essential to develop new tools that afford the required versatility to study these
processes in situ. For this purpose, my group develops nano-electrochemical methods based on scanning
electrochemical microscopy (SECM) that uniquely probe electronic and ionic processes in real time. Using
these and other tools, we are starting to understand fundamental balances between electronic and ionic
reactivity that we hope will have an impact on a various other applications for energy conversion and
storage.

Figure 1. New materials and new techniques for energy storage: Left- Redox active polymers for
size-selective flow batteries. Right- Ion stripping imaging SECM for local in situ battery studies.

References:
[1] Barton, Z.J.; Rodríguez-López. Lithium Ion Quantification using Mercury Amalgams as In Situ
Electrochemical Probes in Nonaqueous Media. Anal. Chem. 2014, 86, 10660-10667.
[2] Gavvalapalli, N.; Hui, J.; Cheng, K.; Lichtenstein, T.; Shen, M.; Moore, J.S.; Rodríguez-López. Impact of
Redox Active Polymer Molecular Weight on the Electrochemical Properties and Transport Across Porous
Separators in Non-Aqueous Solvents. J. Am. Chem. Soc. 2014, 136, 16309-16316.
[3] Hui, J.; Burgess, M.; Zhang, J.; Rodríguez-López, J. Layer Number Dependence of Li+ Intercalation on Few-
Layer Graphene and Electrochemical Imaging of Its Solid-Electrolyte Interphase Evolution. ACS Nano,
2016, 10, 4248-4257.