According to some experts, nuclear power holds great promise for meeting the world's growing energy demands without generating greenhouse gases. But scientists need to find a way to remove radioactive isotopes, both from wastewater generated by nuclear power plants and from the environment in case of a spill. Now, researchers reporting in ACS Nano have developed tiny, self-propelled robots that remove radioactive uranium from simulated wastewater.

The accidental release of radioactive waste, such as what occurred in the Chernobyl and Fukushima nuclear plant disasters, poses large threats to the environment, humans and wildlife. Scientists have developed materials to capture, separate, remove and recover radioactive uranium from water, but the materials have limitations.

One of the most promising recent approaches is the use of metal-organic frameworks (MOFs) - compounds that can trap specific substances, including radioactive uranium, within their porous structures. Martin Pumera and colleagues wanted to add a micromotor to a rod-shaped MOF called ZIF-8 to see if it could quickly clean up radioactive waste.

To make their self-propelled microrobots, the researchers designed ZIF-8 rods with diameters about 1/15 that of a human hair. The researchers added iron atoms and iron oxide nanoparticles to stabilize the structures and make them magnetic, respectively. Catalytic platinum nanoparticles placed at one end of each rod converted hydrogen peroxide "fuel" in the water into oxygen bubbles, which propelled the microrobots at a speed of about 60 times their own length per second.

In simulated radioactive wastewater, the microrobots removed 96% of the uranium in an hour.

The team collected the uranium-loaded rods with a magnet and stripped off the uranium, allowing the tiny robots to be recycled. The self-propelled microrobots could someday help in the management and remediation of radioactive waste, the researchers say.

+ Watch a video of the microrobots in action here.

Research paper

Related Links
American Chemical Society
Nuclear Power News - Nuclear Science, Nuclear Technology
Powering The World in the 21st Century at Energy-Daily.com

Tweet

Thanks for being here; We need your help. The Space Media Network continues to grow but revenues have never been harder to maintain. With the rise of Ad Blockers, and Facebook - our traditional revenue sources via quality network advertising continues to decline. And unlike so many other news sites, we don't have a paywall - with those annoying usernames and passwords. Our news coverage takes time and effort to publish 365 days a year. If you find our news sites informative and useful then please consider becoming a regular supporter or for now make a one off contribution.
SpaceMediaNetwork Contributor $5 Billed Once credit card or paypal		SpaceMediaNetwork Monthly Supporter $5 Billed Monthly paypal only

Argentina's Grossi elected head of UN's nuclear watchdog
Vienna (AFP) Oct 29, 2019
Argentina's Rafael Grossi was elected on Tuesday to head the UN's nuclear watchdog, which is tasked in particular with monitoring the implementation of the increasingly shaky Iran nuclear deal. Grossi beat Romanian diplomat Cornel Feruta to become director general of the International Atomic Energy Agency (IAEA) following the death of the former head Yukiya Amano of Japan in July. The election of Grossi, Argentina's ambassador to the IAEA, comes at a critical time for the Vienna-based agency as ... read more