Scientists have developed a new kind of device that can move charged particles through water using very little energy—and without any moving parts.
This breakthrough could lead to cheaper ways to desalinate seawater, remove toxic metals from drinking water, recycle batteries, and even support new medical technologies.
The research, led by teams from the University of California, Irvine and Tel Aviv University, introduces what they call a “ratchet-based ion pump.”
Unlike traditional systems, which often rely on complex chemical reactions and high energy use, this new device works using a simple, rapidly changing low-voltage signal.
At its core, the ion pump controls how charged particles, called ions, move through a liquid.
This process is important in many areas, from water purification to how cells function in the human body. However, most current technologies are energy-intensive and expensive, which limits their use.
The new device takes a very different approach. It uses a thin, porous membrane coated with ultra-thin metal layers on both sides.
These layers do not block the tiny holes in the membrane, so ions can still pass through. When a small voltage is applied and rapidly switched on and off, it creates a steady movement of ions in one direction.
This effect is known as a “ratchet.” In simple terms, it means that even though the signal is changing back and forth, the system’s structure causes ions to move forward overall.
The design takes advantage of how electricity behaves at the boundary between metal surfaces and liquid solutions, especially at the nanoscale.
One of the most impressive aspects of this system is that it can push ions against opposing forces, which is essential for practical use.
In early tests, the researchers used the device to remove salt from water. They achieved about 50% salt reduction using very low voltage, showing that the technology could be both effective and energy-efficient.
To demonstrate this, the team combined the ion pump with special membranes that only allow certain ions to pass. Together, they created a simple system that pulls salt out of water without any moving parts or chemical reactions. This makes the device potentially more durable, cheaper to maintain, and easier to scale up.
Looking ahead, the researchers believe the technology could go far beyond desalination. One exciting possibility is the ability to separate very specific ions, even those with similar properties. This could be useful for extracting valuable materials like lithium from seawater, which is important for battery production.
The system could also help remove tiny amounts of harmful metals, such as lead, from drinking water. Even very small concentrations of these metals can be dangerous, so a low-cost and efficient removal method could have a major impact on public health.
Although more development is needed, this new ion pump shows how clever design at a very small scale can lead to big improvements in energy use and water treatment. It offers a promising step toward cleaner water and more sustainable technologies in the future.
Source: UC Irvine.
