An international research team working in China has developed a microscopic material that behaves like a predator: it swims independently through water, tracking down and capturing uranium ions. This discovery could revolutionize approaches to nuclear fuel extraction and the cleanup of radioactive water pollution, according to the South China Morning Post.

The Micromotor That Hunts

The material—a light-powered metal-organic framework (MOF) micromotor—was developed at the Qinghai Institute of Salt Lakes, Chinese Academy of Sciences, and accepted for publication on March 24 by the peer-reviewed journal Nano Research. These sponge-like particles are only 2 micrometers in diameter—significantly thinner than a human hair—and are designed for long-term stable operation in water.

When exposed to a small amount of hydrogen peroxide, the particles generate thrust and move through water at a speed of about 7 micrometers per second. Under light, the speed nearly doubles, providing the motors with an extra boost from solar energy. In laboratory tests, they absorbed up to 406 milligrams of uranium per gram of material, subsequently converting it into a stable mineralized form for easier extraction and storage.

"Powered by light, it can move autonomously, making this approach more energy-efficient and environmentally friendly compared to traditional stationary materials," lead scientist Yongquan Zhou told the South China Morning Post.

Predator-Prey Dynamics at the Microscale

During controlled experiments, researchers observed emergent behavior resembling biological predator-prey dynamics. When combining active micromotors with passive colloidal particles, the system exhibited patterns similar to hunting, evasion, and coordinated movement, varying based on fuel concentration. A significant portion of the experimental work was conducted by Ikram Muhammad, a member of the research team.

According to Zhou, the concept could extend beyond uranium to find applications in extracting other strategically important elements, such as rubidium and cesium.

Strategic Context and Unresolved Challenges

The study comes at a time when China is rapidly expanding its nuclear energy capacity while remaining largely dependent on imported uranium. It is estimated that approximately 4.5 billion tons of uranium are dissolved in the world's oceans; however, its extremely low concentration—about 0.003 parts per million—has long made extraction unprofitable. Earlier this year, state-linked Chinese nuclear organizations announced the extraction of several kilograms of uranium from seawater using an offshore platform in the South China Sea, marking another step in the country's massive push for ocean-based nuclear fuel.

Zhou emphasized that micromotor technology is in its early stages. High-salinity environments, particularly salt lakes, currently reduce the system's efficiency, and further engineering refinements will be required for practical application.