Graphene microbots slurp lead from polluted water - CNET

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Humans are pretty effective at messing up everything. Look at all the tech we use. It doesn't come without a cost. Manufacturing electronics and batteries produces contaminants such as lead, cadmium, mercury, arsenic and chromium, none of which is particularly good for living organisms.

To help combat this destructive effect, an inteational team of researchers has developed a school of tiny microbots, each smaller than the width of a human hair, which is capable of removing lead particles from contaminated water more efficiently than previously developed methods.

The robots are shaped like tiny tubes, in three layers. Graphene oxide on the outside absorbs lead particles from the water. The middle layer is nickel, which allows exteal control of the robots using a magnetic field. The inner layer is platinum, which gives the robots self propulsion by adding hydrogen peroxide to the water. This interacts with the platinum, which decomposes the hydrogen peroxide into water and oxygen, propelling the microbot forwards.

The team writes in their paper, published in the joual Nano Letters, that a swarm of the microbots can reduce the amount of lead in water from 1,000 parts per billion to just 50 parts per billion, a reduction of 95 percent, in just 60 minutes.

Obviously this is dependent on the amount of water and number of microbots, but what makes it even more impressive is that the robots can be reused. The same magnetic field that controls the microbots can be used to retrieve them. They can then be cleaned and used again.