UC Irvine Team Unveils Innovative Ion Pump for Water Treatment

A research team co-led by Shane Ardo, a professor of chemistry at the University of California, Irvine, has developed an innovative device designed to efficiently remove salt and other charged compounds from water. This breakthrough, known as a “ratchet-based ion pump,” operates without moving parts or chemical reactions, offering promising applications in desalination, lithium ion harvesting from seawater, and biomedical devices.

On March 16, 2026, researchers from UC Irvine, Tel Aviv University, and other institutions published their findings in the journal Nature Materials, detailing a membrane that allows charged molecules to pass using a rapidly switching low-voltage signal. This approach marks a significant departure from traditional methods that rely heavily on energy-intensive electrochemical processes.

Revolutionizing Water Treatment

The newly developed ion pump utilizes the unique electrical and chemical properties at the interface between metals and liquid electrolytes to generate an ionic current. By modulating the voltage across ultrathin metallic layers on a nanoporous insulating wafer, the device creates a persistent flow of ions, effectively demonstrating what physicists refer to as the ratchet effect.

“Ratchets are nonequilibrium devices that use temporally controlled input signals and spatial asymmetries to drive a steady-state particle flux,” stated Shane Ardo.

The team successfully demonstrated that their ion flux could be sustained against opposing forces, a crucial factor for practical ion pumping devices. They constructed an electrically driven deionization system that achieved a remarkable 50 percent salt removal rate using extremely low voltages.

The ion pump features a structure akin to a capacitor, composed of nanometer-sized pores. Thin metal electrode layers coat both surfaces of an insulating layer without obstructing the holes, allowing ions to flow while applying a rapidly switching electric field. This mechanism’s effectiveness arises from the unequal charging and discharging processes at the interfaces of the metal layers and electrolyte, which generates a voltage to drive the ionic movement.

Broader Implications of the Technology

The research team emphasizes that while their current focus is on deionization, the long-term goal includes achieving ultraselective ion separation. This capability could enhance various applications, including more efficient drinking water purification, lithium ion extraction from seawater, and the recycling of battery materials.

“The ability to remove trace amounts of ions from a liquid mass can be transformative for treating water contaminated with heavy metals,” remarked Gideon Segev, associate professor of electrical engineering at Tel Aviv University. “Even a few particles per billion of lead ions render water nonpotable. A simple technology that can eliminate these ions without removing necessary minerals could improve access to safe water for millions globally.”

The project received funding from several reputable sources, including the U.S. National Science Foundation, the U.S. Department of Energy, and the European Research Council. Alongside Ardo and Segev, the research team included experts such as Rylan Kautz and Ethan Heffernan from UC Irvine’s Department of Materials Science and Engineering, and several researchers from Tel Aviv University and Lawrence Berkeley National Laboratory.

With this groundbreaking technology, the potential applications extend beyond water treatment to critical areas such as battery recycling and biomedical devices, paving the way for significant advancements in multiple fields.