Researchers at the Max-Planck Institute for Intelligent Systems and Nanyang Technological University reported graphene oxide-based microbots (GOx-microbots) that can clean up toxic heavy metals in contaminated water. Tests showed around 95% of lead recovery within in an hour, and these findings may result in reducing the introduction of additional contaminants during water cleaning attempts, and salvaging lead for recycling.

The scientists state that these microbots are more efficient than their predecessors and remove lead 10 times more efficiently than nonmotile GOx-microbots, cleaning water from 1000 ppb down to below 50 ppb in 60 min. The microbots are built on nanosized multilayers of graphene oxide, nickel, and platinum. Researchers say the bots' graphene oxide outer coat captures suspended lead, the inner platinum layer decomposes hydrogen peroxide for self-propulsion, and the middle nickle band allows the machines to be magnetically retrieved from the water. In addition, the autonomous machines can be reused as soon as lead is chemically separated.