Research
Water Purification
It has long been recognized that water is central to energy generation, and energy is a necessary input for all water purification processes. This inexorable link between water and energy, dubbed the water-energy nexus, has motivated the search for new polymer-based membranes for more energy efficient water purification. To that end, the Ganesan group is interested in utilizing both computer simulation and theoretical techniques to explain experimental observation and guide design of future water purification membranes.
In collaboration with the team in the Center for Materials for Water and Energy Systems (MWET), we model polymer membrane materials using atomistic and coarse-grained level MD simulations. In particular, we study the molecular bases of sorption and diffusion of water and ions in membranes, with emphasis on the difference between monovalent and divalent ion transport. Further, we are developing a multiscale framework based on the grand canonical Monte Carlo approach for calculating the Donnan potential and ion partitioning coefficients across the membrane-water interfaces. We also aim to extend our current understanding of polymer membranes to address their anti-fouling properties.
Recent examples of work in this area include the following:
Polymeric Battery Electrolytes
Lithium-ion batteries are devices that can reversibly store and discharge electricity and are used in a variety of consumer applications, such as cell phones, portable computers, and electric cars. Their commercial success is underpinned by their relatively high gravimetric and volumetric energy densities. However, a great deal of work has been done to further improve their energy densities by replacing the anode with lithium metal, prone to failure via dendrite growth, and their safety by finding novel materials to replace their liquid electrolytes.
Polymer-based electrolytes may be a potential component of batteries that will enable these goals. However, they are limited by sluggish ionic transport, increasing a practical battery’s internal resistance, and highly correlated motion between ions, increasing the likelihood of dendrite growth. We study polymer electrolyte materials whose properties will lead to high battery performance, such as single-ion conducting polymers and nanocomposite gels (see the Center for the Dynamics and Control of Materials), and polymer blend electrolytes, using a mixture of atomistic and coarse-grained molecular dynamics methods. Ultimately, we seek to design materials based on the insight derived from these studies.
Recent examples of work in this area include the following:
Physics of Protein-Polyelectrolyte Complexes
Previously available only in specialized environments, diagnostic tools such as blood glucose sensors and water contamination detectors have become widely available via the incorporation of affordable biosensors. One of the commonly used elements in these sensors are enzymes. The sensitivity and shelf life of these sensors depend on the stability of these proteins. A widely used techniqueis to entrap them with highly charged polymers called polyelectrolytes, providing a route to form stable enzyme structures while preserving activity.
However, optimizing the design parameters of the protein and polyelectrolyte to form a stable mixture remains a trial and error method. Intrigued by the importance of such systems, we hope to build a generalized computational framework that can comprehensively elucidate the physicochemical aspects of protein-polyelectrolyte self-assembly. Towards this objective. we have employed a coarse-grained framework involving proteins and polyelectrolytes, using mean-field and particle-based simulations. We aspire to use the insights gained from our simulations to build a framework to rationally guide the design and optimization of protein-polyelectrolyte systems.
Recent examples of work in this area include the following:
