Prospects of Single Atom-Based Electrified Membrane for Environmental Applications

Conspectus Electrochemical technologies represent a transformative frontier for environmental remediation, offering unparalleled advantages such as precise redox control, seamless integration with renewable energy, and chemical-free operation. However, their practical implementation in water and wastewater treatment remains constrained by inefficient mass transport, poor utilization of catalytic sites under dilute conditions, and persistent challenges in energy consumption and overall system sustainability. These limitations are particularly pronounced when treating trace contaminants or pursuing selective transformation pathways. In this Account, we summarize our recent efforts to overcome these hurdles through the development of single atom-based electrified membrane (SAEM). By integrating atomically dispersed catalytic sites into flow-through and electrically conductive membrane architectures, we have successfully coupled atomic-level active-site engineering with device-level transport intensification. We first outline the construction principles of SAEM, highlighting how coordination environment, defect engineering, and membrane architecture collectively govern catalytic stability and site accessibility. We then examine how flow-through operation fundamentally alters transport regimes by suppressing diffusion limitations that dominate conventional flow-by and batch electrochemical systems. Building on these concepts, we discuss representative reaction systems in which SAEM exhibit clear advantages, including peroxymonosulfate activation for micropollutant degradation, in situ production of reactive oxygen species from oxygen reduction reaction for wastewater treatment, and electrocatalytic nitrate reduction for nitrogen transformation. Finally, we assess the stability, scalability, and sustainability of SAEM from a system-level perspective. Rather than focusing solely on catalytic metrics, we emphasize circularity and life-cycle considerations. This analysis underscores that the long-term viability of this platform depends on its performance as a durable, modular, and resource-efficient device within realistic treatment infrastructure. Overall, this Account positions SAEM as a platform for integrating catalysis, separation, and environmental sustainability withinelectrochemistry, offering guiding principles for the development of advanced electrochemical technologies that are both scientifically rigorous and practically relevant.