Research

Mechanisms Underlying Selective Membrane Separation

Constructing membranes with precise solute selectivity is critical for advancing resource recovery applications, such as extracting valuable minerals from brines and recovering nutrients from wastewater. While it is well-established that favorable interactions between target ions and membrane pores can promote their transport over other impurities, the exact impact of these interactions on ion transport remains poorly understood. At the Zhou Lab, we focus on molecular-level membrane design, aiming to precisely arrange these interactions within sub-nanometer pores. Our goal is to systematically uncover the mechanisms driving selective solute separation and to engineer membranes with exceptional selectivity for resource recovery.

Low-Cost, Environment-Friendly Separators for Water Electrolysis

Hydrogen is positioned to become a cornerstone of a carbon-neutral energy infrastructure, yet current production technologies still face challenges. Cation exchange membranes used in conventional water electrolyzers, while offering excellent conductivity, are prohibitively expensive (approximately $250–500 per m²) and pose environmental risks by potentially releasing per- and polyfluoroalkyl substances upon disposal. At the Zhou Lab, we are exploring cost-effective, eco-friendly alternatives, such as polyamide membranes, which are widely used in reverse osmosis and cost less than $10 per m². Leveraging our expertise in materials design, we work to address challenges such as the low proton conductivity of these alternative membranes, optimizing their performance to advance sustainable hydrogen production.

Composite Membranes for Selective Electrochemical Separation

Selective electrochemical separation can be a more energy-efficient alternative to pressure-driven processes like membrane filtration, as the former avoids the need to separate major components in the feed stream—such as bypassing the separation of sodium and water during lithium recovery from seawater. To optimize performance, these electrochemical systems require efficient separators that facilitate favorable interactions with target solutes and maintain a high charge density to ensure optimal current efficiency. At the Zhou Lab, we leverage our expertise in membrane design to create innovative membranes specifically tailored for selective electrochemical systems, aiming to enhance their efficiency and drive sustainable resource recovery.